How much weed does one plant yield?

Many growers wonder how much marijuana one plant can produce. The short answer is “somewhere between one gram and one pound.” But that’s not very helpful, is it? Unfortunately, there is no simple answer to this question. Every grow is different, and many factors like genetics, plant care, and conditions come into play. Here’s a quick reference with rough estimates.

  • Autoflowers can yield up to 100 grams (3.5 oz) per plant, with averages between 30-70 grams (1-2.5 oz).
  • Outdoor photoperiod plants can yield up to 400 grams (13 oz) per plant, with averages between 150-250 grams (5-8 oz).
  • Indoor photoperiod plants can yield up to 750 grams (26 oz) with averages between 300-500 grams (10-17 oz).

The rest of this article will discuss everything there is to know about calculating marijuana yields. Plus, you’ll find some bonus tips to maximize your yield.

Calculating marijuana yield

You will find many cannabis yield calculators online. Some are more exact than others. Because of so many factors, like genetics, light, indoor or outdoor conditions, and plant care, I prefer to stick to estimations.

Years of growing cannabis have led to me doubling the outcomes of my grow over time! So I can tell you how much to expect as a new grower as well as the optimal results possible.

Should you weigh wet or dry weed?

Cannabis flowers must undergo a drying process after harvest. This releases moisture from the buds, along with bad-smelling/tasting chlorophyll, and prevents mold issues. During the drying process, the buds will lose a significant amount of water weight and size, this is normal. 

By the time marijuana flowers are at the consumer level, they have been properly dried. The flowers are then weighed before packaging occurs. Because yield correlates to a final crop value, people do not tally their yield until all of the flowers are dry. Cannabis from vendors can sit in the stockroom of dispensaries before being moved to the display shelf. If it was weighed wet and sold dry, that would make for angry consumers.

Drying your plants correctly will increase your yield
Weigh your dried buds after curing

How genetics affect yield

Not all plants are made equal. While most cultivars are bred to yield well, some stand out as heavy yielders. Here are some core traits to keep in mind.

Indica plants tend to yield more buds than sativa plants. The plants are bushier and sturdier and often grow bigger buds. Go here if you want to delve deeper into the differences between sativa and indica.

Autoflowers are bred so they automatically bloom within just a few weeks. Photoperiod plants bloom when they get less daily light. Autos are smaller and great for beginners, but this does mean the photoperiod plants yield more than autoflowering plants. Go here to learn more about the yields of autoflowering plants.

Some strains are specifically bred to be heavy-yielders. A cultivar named Big Bud is no coincidence! Check out my store for all the high-yielding strains I have in my collection.

high yield seeds

Buy high-yielding seeds

  • Bred to produce large crops
  • Maximize your harvest
  • Pick from several high-quality strains

How much can you yield indoors

When growing indoors, your grow lights are a big factor for good yields. It used to be easy to apply a rule of thumb to indoor growing, as most grow rooms had HPS or CFL grow lights. With LED grow lights popularizing, the easy rule of thumb doesn’t always apply anymore.

Calculating HPS yield

HPS grow lights used to be the standard for professional grow rooms.

For experienced growers, the rule of thumb used to be that 1 watt of HPS light = 1 gram of weed (1 gram = 0,035 oz).


  • A 400-watt HPS grow light can potentially translate to 400 grams (14 oz) of dried cannabis.
  • Likewise, a grow room with 1200 watts of light can yield 1200 grams (42 oz) of cannabis.

Newer growers and less optimized grow room conditions can expect around half those amounts.

600watt HPS grow light with reflector
A 600 Watt HPS grow light with a reflector can yield up to 600 grams of weed

Calculating LED yield

LED lighting has come a long way since the time it was first used in the grow room. The indoor lighting sector has seen increased research and development in the past decade, thanks to the home gardening market. Most people started with blue and red diodes, but this has shifted to a full spectrum of white light as our practical knowledge and applications have increased. 

LED lighting has now surpassed HID lighting in efficiency, which means growers should see an increased yield watt for watt. The yield of a 400W LED is comparable to the 600W HPS. Whereas one gram per watt was considered good with an HPS system, this would be considered an average yield for LED. Growers with the right genetics and a dialed-in system can yield two+ grams per watt with a good LED light.

My article about LED grow lights will teach you all there is to know.

Calculating CFL yield

Some home growers still prefer to grow under a compact fluorescent lamp (CFL).

Growing 5 cannabis plants in a 2×2 foot grow tent with a 2×100 watt CFL will yield about 140 grams (5 oz) of marijuana per harvest.

Dive into my dedicated guide, How many CFLs per plant for more information.

How to yield more weed indoors

Maximizing indoor yields is an art and sport in itself, but you don’t have to apply all these techniques overnight. Each of these tips will help you increase your grow room harvests.

Download my free marijuana Grow bible to learn how to maximize your yield, indoors and outdoors!

How much can a single plant yield outdoor

Growing outdoors in good soil, the right climate, and with great genetics can produce plants with desired yields between 600 and 750 grams (21-26 oz). That’s not the case for most growers though. Most growers aren’t growing professionally tended monster plants. The majority of growers with the right factors can see outdoor marijuana yields of 300-500 grams (10-17 oz) per plant.

How to yield more outdoors

Perfect conditions to maximize outdoor yield means:

Soil vs hydroponic yield

Because hydroponic growing is usually done indoors, we’re going to refer back to the HPS rule of thumb: When growing in soil, expect a maximum yield of 1 gram per watt. Growing hydroponically can yield up to 20% more.

Growing in soil is easier and more forgiving. This is because it not only creates a buffer for error but it also holds nutrients within the soil. Mistakes with pH and TDS will reduce your harvest. When growing in soil, there is room to make mistakes with pH and TDS and pay for it in yield.

In soil, a 600-watt HPS lamp can produce 600 grams of marijuana or 21 ounces.

With hydroponic growing, there is no room for errors. You must be very careful about the TDS and pH levels because the roots are directly in water and incorrect levels immediately affect the plants. Even the smallest error can ruin your yield. However, those who do it correctly will be rewarded. The images below show that hydro plants and their roots grow faster than soil plants.

Hydroponically, a 600-watt HPS lamp can produce 720 grams of marijuana or 25 ounces.

Soil roots day 25
Soil roots day 25
Hydro roots day 25
Hydro roots day 25

Growing a 1-pound plant

Ahh, the elusive one-pound plant!

If you want to grow a one-pound marijuana plant, grow a single plant. You need a 4×4 foot grow tent or other similar-sized space, and a 600-watt HPS grow light. Under ideal circumstances, a 600-watt light can produce well over a pound of cannabis. If you limit your grow to just one plant, nothing stands in the way of growing a one-pound plant.

Growing a one-pounder is a fun project, but there are some downsides. You need to veg the plant for a very long time until the entire floor is covered with leaves and no light goes to waste. Scrogging is the way to go to cover 10 square feet with one plant. You also have to prune and trim your plant a lot to make sure it gets optimal light and doesn’t grow through the ceiling.

If you do everything right, you’ll end up with a one-pound plant like this:

 What does a 1 pound plant look like?
What a 1 pound plant looks like

Learn more about cannabis yields

Now that you know what to expect from your grow, here are more learnings on how to actually harvest these results:

Want to find out how much you can harvest from a few seeds? Hop into my store and download my Grow Bible to fall in love with growing your own.

Happy growing!


Avatar for Robert Bergman

Mr Robert Bergman PhD


Robert Bergman is an Amsterdam-based marijuana grow expert who has years of experience from small grows to massive operations ... See profile

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258 comments on “How much weed does one plant yield?”

  1. Hi there,

    Thanks for your question! Yes, you can cover the plants with tarp or any other light blocking material to trick them into their flowering stage.
    Keep in mind this should be continued throughout the flowering stage or until the days are short enough for it to continue flowering!
    We hope this helps!
    Happy growing,

  2. This is my 2nd year
    Still a rookie lol
    My Northern lightsNorthern lights have been grown for 10 weeks should I try to fool them they’ve been getting 15 hours daylight
    Can i cover the at 7pm and uncover them At 7am their all 45-50 inc

  3. Will the following LED light specifications in a 4×4 with 4-5 plants produce a nice Yield:
    WATTAGE 800W±5%@100-277V
    Core Coverage 4’x4′
    Max Coverage 5’x5′
    PPE 2.8μmol/j
    PPF 2231μmol/S

  4. If you’re using LEDs you need at least 1000 watts, the more watts over 1k the better.
    Try a 1k light and a 300 watt light and see the difference

  5. Coming up to my second year of growing on a larger scale. Thanks Robert and team, I’m x about to retire early and grow full time. This cmmunity is awesome.
    Thanks ILGM.

  6. My led is yeailding a lot and I know my other friend is getting a pound of a plant on led and electric bill is way cheaper no cooling for the lights more room to grow taller .check out black dog 1000 watt lights

  7. 300 watt LED? Are you joking? If you are not using 2000 watt or above you do not know what you’re doing.

  8. All grown using your guides with LED lights, yields vary depending how long I stay in the veg stage 5 week average.

  9. This is a life saving article for people like me who’s interested in growing cannabis. Thank you. [ ]

  10. I’m growing using LED lights in a grow tent. Originally I purchased HPS lighting however it caused the temperature in the tent to be too extreme. Any suggestions for that?? I dnt want my yield to suffer because of the lighting. My two plants are currently growing in the veg state very well under the LEDs.

  11. “Growing 5 marijuana plants in a 2×2 foot grow tent with 2x100watt CFL will cost you around $1000 per year.” .I ran 6 100 watt cfls in a 8 x 6 and it cost me 12 dollars a month. How do you see 2 x 100 watt cfls how do you see them hitting that mark?
    So far I’ve seen fantastic results with my 1000 watt Led, thinking of adding one more for flowering. PAR rating at 18 inches is 1700.

  12. Under a “400” watt led I have had 3 runs. 1 st run had no environment problems and was sea of green almost 12 oz in a 36×36. Second run and 3rd run had environmental problems. 2and run got chopped 2 weeks early due to constant rain. Ended up with close to 7 ounces. 3rd run spent a week in awful conditions and had to be moved around a bunch. 3rd run 7 ounces of really nice fire. Platinum led p450 vegamatrix nutrients, and pure blend when I’m lazy.

  13. HPS is old news, along with whatever BLURPLE LED you were Comparing hps to. New Samsung diodes on Quantum Boards produce better yield than hps per watt. Im sure cobbs arent bad either but i have no exp with them. ILGM should try a grow with LED lights that arent outdated technology. (Any blurple light is outdated ).

  14. How are you measuring yield? Dried trimmed buds, wet untrimmed buds, or some other way. It just appears your #’s are high. Thank you.

  15. Robert I just bought a black dog 1,000 watt led grow light and I have to say these plants are beast! Of course there your seeds! I will send pics around harvest…

  16. Hi I have a plant that has grown only 30 inches tall and it looks like seeds it does not have buds. Can you tell me what it is. I have no name for the plant.If you need pics I can send them.

  17. JIM, MIKE, ED, I Suggest You Go Here: Support.Ilovegrowingmarijuana.Com Our Members And Staff Can Help Give You Informed Advice. We Have A Lot Of Topics That You Can Research.

  18. Plants are two weeks old one sativa the other is hybrid sativa/indica. In 2x2x5.5 tent using LED 600w using fox farms happy frog and ocean forest potting soil, growth rate is good maybe top them to training them next week

  19. I have a ? about lighting. I am currently growing auto flowering Feminized
    plants. I’m using a 600 W HPS. How far above the plants should the lght be?
    Also, I’m using a 2: X 2 x6 Tent

  20. robert can i add your link to my website it is very Informative And exactly what i need to educate my clients

  21. I have a grow space of 3.3 X 3.5 X 8 Foot & 600watt HID Light and Ballast. I Intended to grow just one plant. I will be following the advice in Your Various And excellent posts. I’m an absolute beginner, if there is anything you can advise me on to maximise the yield it would be very much appreciated. I read your posts over and over and will put your advice and guidance to good use in the hope that i can learn and have a successful crop at the end. Thanks for everything you have written. It has inspired me to start this project. If there is anything else you think I need to know about, I would love to hear your views. Once again. Thanks. Paul.

  22. Great piece with great, crisp and concise, easy to read and understand while still chalk full of facts and information.
    Thank You

  23. Thank you about Scroggins, I planted outside for my first time growing this past spring, guess what happen to them when they reached ten feet tall yup some stole them. All summer I kept saying there has to be a way to tie them down, so thank you thank you thank you this will be very useful this year. So happy now

  24. Robert, thanks for thw books, forums and support you have I am a new customer just completed my first purchase from you yesterday.
    However I am not new to growing two years ago I was forced into retirement for health reasons which is why I grow also. I had to switch to all LED lights when I retired so I had better control over my electric use and was very concerned about yields and wow did they ever suffer then I bought two 450 Viparstreca lights to experiment with i had four plants in my experiment and I was so shocked at my yield that grow yielded 5.3 lbs from those four plants. So I immediately bought several more lights from this company. The two biggest lessons were actually stupid simple. Those two lessons were make sure you use better LEDS like the Viparstreca and don’t buy seeds from companies acrosss seas and of course take care of your plants and use a Scrog net.
    I won’t ever buy seeds in the UK again last beans I won’t say the suppliers name here but one time genetics were just horrible the second and last purchase was ALL males both times they gave me the same line of crap and here is their line of BS “its a natural product” we cannot insure your success. Any company that sells me 25 feminized seeds and all of them are males I had the right to ask the company to help their customer. I had given it much thought and read lots of reviews about this company am pretty excited to pop those beans and see how we do.

  25. Just curious. Not sure if it was heavily mentioned we can’t forget strain and genetics also make up for a large majority of the harvest/yields. For example no special lights, spacing, nutrients, training techniques, Co2, etc matters if the genetics/strain isn’t right for your grow. Going into this example, if you have a medium tent or small space you don’t want to grow a naturally tall growing sativa. It would be better if you grew a shorter indica or hybrid. And secondary into genetics, certain strains as you mentioned i believe, have higher yields than others no matter what you do. Also for timing as well because some strains flower faster. I just wanted to take these things into consideration for yield amount. I personally grow with 1 1000w LED and sometimes add a second 600W. I’m month from harvest on two 5 gallon plants. Not sure of strain but am looking forward to sharing results. Plants have been healthy entire grow and have multi colas from training. My soil is a mix of plant based compost and potting soil (low nutrient). I appreciate the free knowledge and community exchanges

  26. Back in the 1970’s a friend and I grew a Colombian gold plant in the los angeles national forest. It was 12″ tall and produced six and a half pounds of sensimilla!

  27. started germ. seeds will not sink so far 0-10 in paper towel at 75 degree temp 48 hours nothing!!!! other seed co 25-25 hit. whats wrong with yours WHITE WIDOW FEM AUTO

  28. Hi Lou aka the derelict here ? I’m wondering what properties the male plant adds to a strain when crossed reason I ask is that I crossed a sativa with female kush kush l now have two females growing 1 month in flower just wanted to know what the sativa male will add male is a local strain purple bud 2 also has anyone heard about kush kush strain and where can I find them

  29. As long as you keep them cold, dark and dry the seeds will be viable indefinitely 🙂
    We’ve heard of seeds laying in a corner for years that still popped up! We do advise to use them within 12 months just to be sure.
    We suggest keeping the seeds in a dark container with silica packets or rice to keep them dry and storing them in the fridge for as long as you are not using them.

  30. Marc Briggs,

    Not much…Sorry 🙁 You get out of a grow what you put into it. Happy growing

  31. 1st time grower and doing everything natural , no growing lights or special nutrition , how much should I expect

  32. I wouldn’t recommend sour de for west time grower but you never know I’m sure it’s happened. I would recommend White widow. Very easy to grow hybrid with nice yield and an impressive social smoke.

  33. Whats the average amount you get your first harvest per plant if you’re growing indoors any advice because im wanting to get a dealzer grandma secret grow box that grows nine but im gonna grow just give any advice?

  34. I am in week 5 of flower and expect to harvest my first plant in a few weeks. SS (not ILGM yet, I have GDP for grow #6). Thank you for all your invaluable advice, AWESOME customer service and setting up the forum to ask questions/share various ways to overcome issues.

  35. I want to grow a personal amount on my tiny deck, in Missouri. I want Jack Herer and Harlequin. Is this even possible? Can you please reply via email?? TYVM!

  36. of course the estimates are some what unrealistic even the guy with 1000w and c02 gets maybe a half pound at most with a 5 gallon bucket ive herd of once the guy using a screen and getting around a pound from one plant but its very rare and that was using coco. Alot of people swear hydro yields the most but I can tell you even with canna and canna nutes and c02 that guy does not get pounds per plant I had a guy who knew that guy try to tell me oh c02 this and that burn it and stuff.

    For one c02 raises humidity so the guy has to fight with that and powdery mildew because he likes to grow kush strains so in the end some of the bud is dense but moldy.

    what I get for a yield is around what the guy gets with the fancy canna nutes and I do not use full coco mix.

    I use a 7-10 gallon bucket with 400w hps and the rest led side lighting which brings me up to 1000w of actual light I do just one or 2 plants I top the plant once depending on what strain it is. I have used a screen tried without the screen with no noticeable difference.
    I pull half pound plants indica sativa no matter.

    I have used heavy 16 a+b nutes for the last couple grows and I get decent chunky buds.
    I don’t seem to notice a difference in yield with my setup as opposed to just 1 1000w light.

    I had a 400w hps setup before and did 3 plants got maybe 4 oz total with t12 side lighting using fox farm nutes and soil. With this setup the hps plus the led I see no difference in the yield im getting I don’t care what anybody says.

    I know if the led lights did nothing at all then id be lucky to get the 4oz from just the 400w hps.

    I just chopped one and looks like 4oz of just colas I should have around 7 or 8 oz when its all chopped and dry which is not bad at all. Trust me it is not easy to grow a big plant without problems

  37. Jamie,

    You need a 7′ foot tent. You need air and air flow. 1 -2 plants in a 4’x4’x7′ ternt would probably fill it. 1 600 for this size tent. I advise you to join and start learning from the expert staff and friendly sharing members there.

    Happy growing, lw

  38. so far learning a lot about what it takes and what you need etc for a successful grow and loving all the information ILGM has. Quick question;
    I’m wanting to maximise yields growing 4 singles (want to try achieve 1pb+ each plant) and I was wondering if it would be better putting them in their own tent or 1 big one. I plan to use 4 600w hps lights and start with soil as its my first grow. Lastly if the bigger tent is the way to go or the yields should still be the same what’s the recommended tent size. I’m looking at either getting 2.4×2.4×2 or if I go bigger 2.95×2.95×2 will that give me bigger yields. am going to use the SCORG METHOD

  39. so far learning a lot and enjoying reading everything ILGM has to offer as I am beginning to start my own journey. Quick question, i’m looking at getting a tent big enough to grow 4 babies, using 4 600w hps lights using the scorg method. I was wondering if i would get bigger yields using single tents or if I was to get 1 big one (a bonus and save on the set up). if I was to get a big 1 would it be better to go for a 2.4×2.4×2 or 3×1.5×2.3, will be growing with soil too as its my first time but plan to go full hydro after. thanks in advance and look forward to learning more and making future purchases !!

  40. I’m a first time grower, 800w cob led, living soil from roots organics, fertilized with only Papa’s perfect poop. Nitrogen gains were with white dutch clover. Would love to send pics.

  41. Dale,
    24/7 is a bad idea. I am surprised you learned that at ILGM forum. The plant needs rest. Expert growers never use 24/7. I personally use anywhere from 14/10-18-6 depending on the experiment but, never over 20 hours of light. Darkness is reqwuired to allow the plant to rest and transpiration and root growth is most vigorous in the dark cycle.

    So; No adding a dark period is not going to hamper growth it shoud have been used to stinulate all growth fron the beginning. It is a misconception that more houts of light help speed growth; In fact it stifles the roots and peoper photo synthesis cannot occur without at least 6 hours of darkness. Some growers like to push this to 20 hours with clones but, never seedlings.

    Happy growing.

    p.s. This should have been asked in the forum 😉

  42. 1st time grow…using 300 watt led in a 2x4x5 tent. I have one set up for vegetative and another for seedlings/early vegetative plants. Currently, I am growing 2 orange og in separate bushel laundry baskets. One is in fox farm ocean and the other in worm castings. We just transferred them out of 2 gallon pots and seem to be doing well. Both are 6 weeks old and seem to be doing well (10-12” tall and 20” total). I have been 24×7 with the lights from the beginning.

    Now to my question, would giving them a 2-4 hours of dark a day hurt or hamper in your opinion?

    I have enjoyed and learned so much from ILGM forum as I can see others plants in their various grows and am able to see how it could potentially effect mine!


  43. I have a 2000w led light.. do you think its a good light for growing indoor.. i have a green room of 4×4. Can you guide me about at what distance I should keep the light from the plants..

  44. Dean Wood,

    Yield is directly proportional to experience, grow methods, and maintaining a healthy environment. With that said; I cannot predict how well your grow will go. That is a small tent and maybe you will be able to fit 4 clones in a SCROG.

    join us at for excellent expert advice. 🙂

  45. scott sarli,

    I am sorry to say you are incorrect. Wn experienced grower can get over aLB. in a 4×4′ tent. In fact; I once got 1.5 LB. from 2 Gold Leaf plants in a 4×4′ space.

    Now; One might say; “It does not happen all the time”.

  46. Jamie,

    No one can predict what you will yield. I can tell you this. Auto flowers yield less than feminized or feminized seeds. Much less.

    Happy growing

  47. I have a 2.5ft tent running 2 x 250watt HPS light over a 4 clone scrogg, skunk #1 how close to 1 pound of weed will I get??

  48. I just grew a blue rino under a ‘600,it looked close to you pics.been doing it a long ,have a card.I’m 60.I got 6.5 of beautiful nugs. no small shit.I dont’t buy getting a lb out of a 4×4 tent,just to small.enjoy

  49. I bought the autoflower mixpack that has the Amnesia Haze auto, the Blueberry auto, and the Northern Lights auto. I plan on planting them in pots with high quality soil. I was wondering about how much yield I can expect out of one of each of those plants. I don’t plan on doing any special grooming. Thanks for any info.

  50. K Erickson,

    25 oz. per plant could only be accomplished outdoors. Indoors it would take a high level high $$$ grow to make that. Top yield indoors as a benchmark is a LB. Most indoor growers may acheive 5 oz. per plant. Only expert growers can get max yield indoors and the cost of equipment is high. Also; All this is subjective because it all matters on the quality of genetics, grow methods, and overall experience.

    yield = whatever you decide yo keep and use from the plant. Medical growers making coco oil and such will use leaf as well as flower and this would be coounted as yield but, in general yield = buds.

    weight = dry organic matter

    It is possible for resin glands to appear on leaf and stem on parts of the plant.

    Happy growing

  51. Anonymous User,

    No one can truly guess what your yield will be. There are so many variables that go into growing high yields. First; Experience. Learning how the plant reacts to your methods will help you grow stronger higher yielding plants. @nd; Genetics is key. I suggest you join our forum and let us help you learn to grow successfully. Happy growing

  52. Robert Young,

    First; IN order for us to help you; We need you to join our support forum. The instruction you need is beyond the scope of a Blog comment, so I invite you tro join us here for expert and friendly guidance for successful growing. 🙂

    As far as Leaf and bud. You can smoke the leaves as well as the flower. Most of us are now using the trim (leaves and smallish buds “larf” to make infused coconut oil) Hope to see you at ILGM forum.
    Peace, latewood

  53. The questions below will sound like questions with obvious answers. But within my circle there are different interpretations of your yield comments. I know yields can vary. But for the questions below let’s use your proxy yield of 25 ounces per hydroponically grown plant. QUESTION 1: Is the 25 ounces per plant: A) a one harvest yield for an individual plant grown over one grow cycle of say….73 days totaling 25 ounces or B) an annualized yield for growing one plant every 73 days for 5 grow cycles per year (365 days year / 73-day cycle = 5 grow cycles per year) totaling 25 ounces (5 ounces per plant x 5 grow cycles)? QUESTION 2: Is the 25-ounce yield for flower heads only or does it include other parts of the plant? QUESTION 3: Is the 25 ounce yield a dry or wet weight? QUESTION 4: Beyond the flower head, is there any meaningful resins elsewhere in the plant? Thank you.

  54. Hello, i am planning on growing some ‘Black Widow’ and just wanting some feedback please.
    These are the following equipment that i will be using. – How much yield can i expect?
    1. Grow Tent – 120cm W x 120cm D x 200cm L
    2. Compact Fluorescent – 2 x 250W | 2700K & 6500K
    3. And the recommended nutrients and what not.

    Also another question, would Canna Rhizotonic root stimulator be any good on a seedling or is it not meant for that?

  55. another question when you harvest your plant you only talk about buds can you also harvest the leaves and smoke them or is it only the buds???

  56. this is my first time to grow I am having a lot of problems out of 9 different plants I have germinated the seeds fine planted them had the seedlings come up the stems are so small they cant even hold up the first leaves I read about stretching but I cant figure out if it is my lighting I have I small led red/blue grow light 1 40 watt led bulb and 2 60 watt regular bulbs hanging in a grow tent I purchased online at wish I have a small fan blowing into tent I feed them a plant food every 2 weeks and water lightly 3 times a day I do not have a good green thumb out of the 9 I have lost 5 of the plants when they are about 4 inches tall I myself do not smoke it is for my wife medical weed I myself am 76 years young am set on a real poor income so the street cost really eats into our income the cheap stuff we buy had some seeds so that is how I tried my luck which there is none so far any way you can help would be appreciated thank you.

  57. In uruguay the common unit for pot is “the 25” referring to a little brick of 25 grams of hard pressed cannabis plants, or moire recently when cannabis was legalised, 25 grams of non pressed cannabis buds.

  58. Sorry Robert. You are focusing Too Much on the larger indoor grower. I have two plants that I grow in my basement. I don’t have 400 – 1000 WATT grow lamps nor can I afford all these set ups you suggest. The calculations and ratios you are giving are not relative to what I would like to do. I have read half of your grow bible, and again, you focus a lot on the high yield grower. I’ll be happy with 2 -3 ounces which will save me $500.00 street value here in N.J. Not to diminish your teaching, but this is too technical for me.

  59. I started off with 2 large plant pots and got about 1/2oz max. Then I got a mega bag from sports direct and planted one plant and got 3oz.I recycle the compost to.

  60. The distance between plants is determined by the grow method, and size of clone when added tot eh garden. As a general answer with little input to go on, I suggest 3-5′ apart.

  61. Hey,
    I was wondering if clones need to be a certain distance apart from each other when growing outdoors. If so, how far apart should I plant them?

  62. Anthony,

    What do you mean; Without getting a set up?

    If you put nothing into your grow, then you can expect as much return. Temper your yirld unless you plan on doing it right. God luck 🙂 Perhaps you should go and join our support forum. We can help you grow successfully without doubting yourself along the way. See us here:

  63. SCROG is great technique Indoors or Outdoors.

    Most indoor growers using grow tents use SCROG for their grows. It is definitely not an outfoor only method. Peace

  64. Gday Robert,
    I’m planning my first crop but just plan to stick a few plants in pots in my lounge room without getting a setup, is this a good idea?

  65. I reckon the “scrog” method is great outdoors, since it’s possible (and desirable) to keep the growth with as low a profile as possible. One plant with the branches pinned down as they grow is a lot safer than simply allowing it grow tall enough for people to see over your fence.

  66. ChrisDawg and Dave,

    Full spectrum lights are the best spectrum and being proven everyday. Yes Blue MH HID is generally used for Veg and Red HPS HID in flower. HOwever; Higher terpine levels, and THC% Using Metal Halide or Full Spetrum white light (LED)

    There is hardly ever any green in the lamp spectrum. And Blue and Yellow produce green

    Happy go lucky growing 🙂

  67. Newfie,

    Of course you can. Although most growers do not find it necessary due to having unlimited light; You could SCROG outdoors if you want to build it and work it. 🙂

  68. Is it possible to do a large Scrog, out doors, using natural light.
    Seems it would be fun to try.
    Wonderful website.
    Thank you

  69. hi this is the first time i have ever been here i have searched other sites but this one has already taught me alot i have grown out doors twice first time they had buded but got blown over so i took them in second ttime still paid no atension but did put some manuior down about half way through the season going to spend some time on them next year

  70. Red and Blue make Purple. The only Green is your plant. Not to mention that Blue is more vegitation, and Red is for your flowers. Your success is a miracle.

  71. Ok, so I’m retarded. I reread my post and obviously red and blue doesn’t make green but the red,white,and blue lights mix the spectrum so you do get green light from it. The specs mix all the way down the par and it gives you a bad spectrum and those lights can be very pricey. Get a red LED for veg and a blue for flower and see the difference. I’m sure you guys can tell how potent my weed I when I have to repost 3 damn times to just get you the info. Happy growing!!

  72. I’ve been killing it with LED lights! It’s the way to go!!!! The problem is all LED lights aren’t created equal. The ones that work have red only for flower and blue spectrum only for flower;dont use mixed spectrum. Think about my growing friends the colors red and blue make what color…green. When the red and blue start mixing a few inches down from the light as the par spreads you’re soaking your plants with green light with fragments of red white and blue spectrums screwing your yields. Led is way better than HPS, I’m yielding over a pound per plant,better quality, and cheaper electric bill.

  73. Hi Robert, I just started reading your grow bible after I found a blueberry kush seed in some real good bud. I have a beautiful female that I give a lot of attention to. She is 8 weeks old and about 8 1 2 inches tall. I use your information& my gardening skills. I am using sandy soil & what I call hillbilly grow, since I only spent $60. I am very grateful for the information in your grow bible. I want to send pics do I do it through e mail

  74. Thanx Robert this is the most awesome free growing website That I’ve ever seen I suggest it to all first time growers. Listen I’ve been doing this for 15 years and still downloaded this free growers bible E-book I love the in-depth love that is shared yes I call ed the info love because the founder of this awesome “GEM” of a book shows his love for getting newbies comfortable with how easy it is if you reSlly have the gift of the canbabis Green Thumb “Peace Love & all that good stuff I’m out
    Jim Bates here have a wonderfully Blessed first grow.!!!!!!!!!!!

  75. Hi James, nice platform you’re building with CAN! You can syndicate the article but pls give proper credit to Robert Bergman including link back to the original content.

  76. Johnniebeebad,

    I have to smile. Imagine an old grower wanting to help you learn the things you need to know in order to grow successfully. I am smiling. Do you wan to know why?

    You are already outdoors and you are now needing to figure out how to nurture your plants until and through harvest. So; The question is not how your plants will do; It is: “How do I get to a successful harvest, now that I have started these plants outdoors”?

    Join us at

    We will guide you to a successful grow. 🙂

  77. I use one to start my seeds and it works end up with some very strong roots to start your plants with

  78. Ive just finished a Hydro Ebb and flow grow with one Royal Critical Auto Autoflowering plant. I used a 400W Led Two COB lamp. The final dry yield was 130 Gram(4 1/3 Oz). Not too shabby for a first time grower using home made hydro gear. The lamp was purchased on eb*y for about £90 (Uk Sterling). THe wuestion on everyones mind….what was the product like. Very nice….very nice indeed. It stands up to and probably beats anything local dealers in my area sell so the experiment was a complete success!!

  79. I am a first-time grower outside in pots in soil I have five different strains co
    Kushage. Cinderella 99. grape Escape. sweet tooth. and Bubba Kush. Are these good strains to grow outside

  80. I am a first-time grower in soil in pots outside my plants get sun from the morning from about 8 a.m. till 3 p.m. and then get little spurts through a tree after that… 4 of my plants are going very nicely but to seem to be struggling in size they look very healthy but they are just not keeping up with the others do you think they will catch up eventually

  81. I am having problems with getting my plants to get beyond the sprouting stag
    The germinated seeds grow to small plants with two to four leaves on top and then just die. I folowe the grow bible but the pants still die. Can’t figure it out..

  82. dark warm area for 16 18 hours in a bowl or cup of water then switch to a moist napkin in a ziplock untill the root is long enough

  83. Hello Money85. I could give you some advice but I don’t know what you want to know. I’ve been growing hydroponically for two years and I’ve had a few hiccups along
    the way. But I do learn from my mistakes and hope to not make the same one twice. Give me some questions and I’ll try to help you.

  84. I’ve never grown in soil. Hydroponics is the way for me. I get bigger yields with water rather than dirt. What seems to be your problem?

  85. Hello elaine. Do you have experience with soil? Could u maybe help me out with my grow quick?

  86. Hey paul, can u help me out with some things or someone? This is my 3rd grow i. Soil

  87. I have 4 plants (2 different strains) in my 4×4 tent. I grow hydroponically. All plants are in a 20 gallon cooler. I have a water chiller keeping the water at a constant 70 degrees. I have a Mars II 1200w LED lamp with both lights on (veg and bloom lights) for the 12/12 light cycle. And to complete the puzzle, I have an o2 Grow oxygen emitter (with 2 emitters). Harvest will be in 3 weeks. I am on track for at least a pound. This is my first grow with all the right equipment. I had one hiccup with one of my timers. The plants did not have any oxygen for about a week until I discovered it. But it only affected one section of one plant. No big deal. I’ll be happy with this grow. I learn something from every grow. Next grow will be the perfect one!

  88. How many seeds should be placed in each container? For example one seed per bucket or two seeds per bucket and so on?

  89. Agreed. i have never got a yield of 1gm = 1 watt in 30 + years of growing indoors. more like 0.8 per watt

  90. 4/28/17
    Hey Rob
    first time grower. Got autoflowers in February and by April they are blooming. I germinated & grew them indoors under 24 hour light, in Miracle grow Garden soil. When I replanted them I added used Coffee & Tea leaves, Sand (for drainage), crushed eggshells to Miracle Grow Garden soil. A few weeks later the 2 foot plants flowered. I quickly put them in larger pots with the same formula (dried coffee/ tea leaves, crushed eggshells, sand with Miracle grow garden soil and this time some potting soil as well). and shifted to 12/12 sunlight and complete darkness. Soon I moved them outdoors (live in the deep south) where there is plenty of sun, warm weather. If it is going to rain i put them under the glass table outside. If not they sit on top. Only water the soil and stopped spraying the plant. Gave the prescribed dose of “Blooom all” and the flowers are now over an inch and rather thick… on a couple of plants while they vary in size on the remaining ones. I clipped a couple of flowers, oven dried them at 200 degrees for 20 minutes. they are great. I check the others with lens used by geologists and the ‘dew drops’ on the flowers is clear but profuse. the Pistules have turned red and crumpled up but i am waiting for the ‘dew drops’ to turn a shade of yellow to amber before I clip them this time using a dark .
    Now they simply sit out under natural day and night light. I water them making sure the soil stays fully moist.
    closet to dry them. Few questions:
    If I re – pot them to larger 2 gallon pots while they are flowering will they grow as a plant and continue to flower? Right now they remain at 3 feet in pots less than 1 gallon.
    My first “harvest” of 3 flowers was on April 24, today it is the 28th. Should I wait till the ‘dew drops’ turn a yellow shade before harvesting the next bouquet of flowers?
    -I guess I could get 2 to 3 bouquets till October. Would my guess be right?
    -Any tips or advice for me?

  91. Hi Mark ohara pleasure meeting u got all that u sent….thank’s amazing ur. knowledge on growing…will be placing an order tomm….thanks!

  92. I have had good results with household led bulbs in a small grow cabinet. My box measures has 3.25sq ft of floor space (18x26inches) and 60 inches of height. I have yeilded over 5oz with 2 plants in deep water culture using 12 Philips soft white led 100w equivalent bulbs. They use a total of 175w.

  93. Dan,

    Although LED lamps systems have made great strides. Many expert growers still consider HID lamp systems superior. The cost per watt is vastly different. LED lamps matched in watts are approx 5 times as expensive.

    As far as the example you posted. Depending on where you live; Electricity costs vary. IN relation to the cost of $50.00 per plant example; One Gold Leaf grown under a 600 watt Digital lamp system will yield 6 oz. per plant in just a simple 5g cloth pot. That has a medicinal value of 1500-1800 bucks per plant. Sounds like it would be worth it to balance $50 bucks against the massive savings from buying Meds at a pharmacy.

    Perhaps you should join our support forum. We have many helpful friendly, and sharing members who can share their experiences with you.


  94. Actually more of a question. Before I found you and your site I bought a Sun System DIamond 315 watt LEC light for my 3×3 tent. I am brand new to the hobby but I am doing it because I am retired and I have the time to do Hydro plus I love watching things grow. So is this light (like you said LED) inefficient compared to HPS ?
    Now my next question and I feel stupid even asking this but I don’t understand this theory. It seems if the electricity costs you $1000. each plant would cost more than $50 to produce.
    Growing 5 marijuana plants in a 2×2 foot grow tent with 2x100watt CFL will cost you around $1000 per year and yield 0.25 pound of marijuana per harvest. With 4 harvests per year, each marijuana plant costs about $50.

  95. Great article, especially for the newbies you are teaching, Robert. Advice like this will keep them from making all the mistakes most of us made starting out. You are really giving a lot of value with your free lessons. Wish this info was available when I started in the 60’s.

  96. Mike,

    That is a small tent, and it will work for veggin clones.

    As far as mixing compost or manure with Miracle Grow; That soil might be too HOT. Be careful.

  97. Hi new here. I have always growing outside so new to indoor growing. My plan is to start indoors and move to outdoors with clones. Have a tent 27x27x63 inches with a mars 300.Is that enough light? Using soil I made. Compost and Miracle gro. Going to finish off some plants indoors. Any help would be nice.Happy growing all.

  98. Daaniel,

    It is posted in the article above that the approx. range of yield for a 250w hps grow is 80-150 grams. The size of tent and plant count is moot.

    We shoot for a gram per watt. Most growers are lucky and happy to acheive 1/2 gram per watt.

    Happy growing.

  99. I grow indoors using a combination of LED and CFL lights. My 5′ x 5′ grow tent is lit with 2 165 watt led lights, a 250 watt CFL and a 125 watt cfl. I don’t really know what I get per plant. I do know I get way over 1 gram per watt. Each variety and harvest are a little different, hell each plant seems to have a personality. Oh, I also use “smart” pots, no root bound plants and I use a very old and very basic nutrient brand. Also my dried bud weighs a minimum of 25% of harvest weight, usually closer to a third. Happy growing

  100. Hey guys.
    Just wondering a little more info on grow lights and room sizes.
    I am currently using a tent that is 800mm x 800mm x 1600mm with a 250w hps and mh globes for flower and veg. My question is roughly what can i expect to achive being a beginner and in comparison a advanced grower.
    Thanks again for the help as always

  101. Thank you Robert, I owe my education to you…. This is the best site on the subject on the planet, I enjoy your articles and for free or a few bucks one can develop a serviceable skill. I got to go to your store and buy some more seeds and stuff …. Thanks again from the other side of the planet.

  102. chris. Only one plant would fit in that box and you would have to do a SCROG grow to make it work/. 36″ minus a pot, and a lamp barely leaves enough space to veg 1 plant for a month; Much less attempting an entire grow or a grow with multiple plant A 24″ x 24″ box would be great for seed starting and rooting clones. 🙂

    Happy growing!

  103. But ain’t the most determining factor is the strain your growing. Some strains just don’t produce as much as others do they ?

  104. I have yet started my grow,but I have a question. I built a 24×24×36tall grow box made of wood. How many plants can I put in there using a 250 watt HPS bulb

  105. Autos generally take 110-120 days to finish in my experience. I harvest by monitoring trichomes for potency. I suggest you join our support forum and we can help you bring your plan to life. Just @latewood when you get there, and we will get started.

  106. leve,

    I find that most autos take 110 days minimum to finish properly. I suggest that you join our support forum where we can all discuss your plans and give you sound advice. When you join, post an @latewood so I will know you are there. We can help.

  107. Lou,

    An aero garden is not big enough to grow big marijuana plants to finish. I believe this unit was meant for growing herbs on you kitchen counter. Why don’t you join us at We have an excellent support forum. Peace, lw

  108. i need also a little help if anyone can do it…i am new to practice growing.. i have been reading for more than 5 years but i didn’t had the chance to fulfill my dream until now.. anyway , i Have a room of 2x2x2M , 2400W led , 16 pot of 21L each Hydroponic RDWC system good ventilation system and environment( i know that this is a very good kit for photosynthesis grow “normal plants not autos”)but i dont have more than 4 month from seed to harvest).. i want to grow autos for fast harvest less than 13 weeks (from seed to harvest)exept if there is other way..i have redden some article that take me to a conclusion about the strain i need(amnesia haze autos) i am not sure yet and that is why i need your help…
    My goal is to get 2kg of dried bud if possible in 3 and half month + 14 days dry =4 month total from start to finish..
    If anyone can help me out to reach my goal please …all its left is What strain , nutt schedule , what i have to do to reach my goal?Any help will be appreciated !
    Thanks Regards Leventis…

  109. Thats a good question.. I wanted to make this question but my friend here did it already…If anyone can please help us out.. what they mean with auto seeds when they say you will get 500g/m2 (they mean DRY OR WET?) if its wet then this is no possible coz you will get 25% of your wet bud ..that mean in 1m2 u will get 125g of dried bud? or when they said 1 wat per g they mean wet or drie?

  110. My question is about yield. When you say “an average of around 5.0 to 10 oz (21 for advanced growers) with a 600-watt HPS lamp in a grow room that measures 4 x 4 x 8 ft.” is that at harvest or dried?

  111. I plan on growing with leds for the next time can you refer a cost effective one and if you have one kind goind and getting ready to flower is it unwise to add more light of a different kind? Or does it hinder growth….

  112. I think I have over feed my and I am struggling to get them back will they come back or not can you tell me please

  113. Mark,

    Yield is not predictable unless you have an established benchmark that would be needed to make an informed guess. Otherwise; It is just a guess.

    The yield depends on the skill of the grower, and the methods, time, and investment put in to provide an optimum result 🙂

    Happy growing, And; You won’t know until you grow!

  114. Should of said also that I’m going to lollipop them and supercrop them as well as top them, they are on a 18hr light sequence at the moment then switching them to 12/12 hr.

  115. Just set up my grow room with a 1.5m2 x 2.4m2 x 1.8m2 tent, it’s got 2 600w hps lights, an outside air source located at the bottom left hand side and a 147mm extraction vent fitted with a 24omm x600mm carbon filter. It’s temperature and humidity controlled with 8 kush plants. My first grow but I’ve got plenty of help from experienced growers plus I used to grow show tomatoes. What do you think my yield should be roughly ?
    Thank you in advance.

  116. We Americans use both every day. With Marajuana we typically use grams and Ozs. For our dispensing. I’m older and this is the way it’s been done since the 60s.

  117. Are the led grow lights worth using? Just starting my grow operation though they might use less electricity. Heard they were very good but not sure this person knows what he’s talking about. Thanks

  118. I just switched to led lights kinda as an expirement my plants are just starting but I was wondering if leds are a good or bad idea

  119. Growers experienced and new come together to learn from eachother as well as from our expert grower. You can have a look around here and sign up with the top-right button.

  120. Hey i downloaded the bible & plant care guide, but just curious on what the support forum is and how to join, thanks

  121. Why? LED is beyond capable to produce quality mj plant from seed to harvest, sovwhy the B’s concerning; LEDs!? Your answer please… And doesn’t need 2include; I, or a business sooner, or buddy sell MH, SPL as your rational for propagation of ‘your’,choice of commercial market technique, you know FACTUALLY… most areb ‘small’ independent growers for their supply, period… why the Allegiance to the money whores?

  122. Hi Mr loony,

    I have some questions about cannabis growth and would be grateful if you could please guide me.

    Best regards

  123. fishhead,

    You need to read up on LST or SCROG method of growing. Download and read our Free Grow Bible. Or; Join oursupprt forum. 🙂

  124. stephen,

    Place them in a cool dark place or in the door of you “fridge” behind the salad dressing. 🙂

  125. Im limited on my hieth for my light & can only grow (space enough for 2 plants). my question is how can I make it work with a 3x3x4 or 5?? reduce the 600 watt to 250 & try to bush them instead of growing tall?? thanx ..

  126. I’m a first time buyer and grower,so much great info here, I’m filling up a small note book. Just ordered Fem. white widow and plan to grow out doors upstate N.Y. wont even be able to plant until late June so this should be interesting for grow to harvest time , I”ll have about a 10-12 week window if my seeds arrive as scheduled.
    My question is that if I don’t use all my seeds ( I only plan on planting 3-5 plants) how do I store seeds for next year

  127. We know what grams are we do use metric just not for drugs in America not so much but in uk most things are metric ok

  128. Hi Erick. If I have read your question correctly, you are asking how many plants you can grow in a 2m x 2m space. I don’t know if this will assist you or not. My last grow I grew, 32 red devils & 8 White Rhino’s in a 3m x 2m space under 6 x 6oo Watt HPS & one 1000 Watt HPS. This yielded just over 200 oz’s (I’ am old school so my Oz’s are weighted in at 30 grams each) of dried plant that were on a 18/12 light cycle. 2 months on grow, 6 weeks on flower, plus two weeks to dry correctly. Hope this helps in your calculations.

  129. Marilu,

    growing is a series of personal choices. This is one of them. It all depends on how much space you have. It also depends on your grow experience; The quality of environment you produce for your plants, and many other variables.

    Perhaps you would like to join the ILGM supprt forum, where we have many knowledgeable members and staff to help you all the way through your grow 🙂

    Happy growing

  130. I’m planning on buying the set to grow along with seeds and I read that you can get more from one plant than you can with 4. Which would you recommend?

  131. Mike,

    Different strains grow at different intervals. There is no perfect formula.

    You will need to keep lamps 24-36″ from canopy depending on how hot the air space between the lamp and canopy is.

    Best to think about training your plants.

    Best thing for you would be to join our support forum. Many growers have become experts at SCROG, and are will to guide you. 🙂

  132. devon,

    You will do OK with a 250w CFL. It is a bit under powered but, will allow you to grow successfully without heat issues.

    If you want a bigger harvest; You will need to invest in more lighting, and exhaust systems to manage to heat and humidity. 🙂 lw

  133. I have a 60×60×80 size grow tent. 1 300 watt led light 1 45 watt led light and a 400 watt hps light. With 5 plants out of 6 remaining after take the male out.i am a first time grower nd im still not sure how to scrog yet ive seen plenty of videos I have 1 plant thats almost 4ft tall and its about 10inches away from the hps lamp while the others are about 2ft away from all the other lights how far should the tall plant b away from the light during the flower stage I am now 2 weeks into it and they should stop growing now right?

  134. Hi i am a first time grower, i have a 3×5 grow box that i made… I also have a 250w CFL, i plan on growing 3 or 4 plants….. My question is do i have good lighting for a great harvest?
    Desperately in need of help

  135. In regards to outdoor potted plants,

    If you plant in 1 yard of good quality soil, get them vegging early inside before planting outside and then keep on top of nutrient input and overall health and training, with plenty of sunlight, you can expect to get between 2-4 lbs per plant, depending on strain. If 2 yards, double that. Ive seen 10 lb plants if all the conditions are just right.

  136. Generally, 0.5 grams per watt is more realistic. Also, you get a better ratio of yield/wattage as you go up in wattage, i.e. you’re more likely to hit 1 gram per watt under a 600W or 1000W HPS than a 250W or 400W. That’s because HPS lights are more efficient at higher wattage outputs.

    As for the outdoor stuff, medical growers in California that are limited to 25 plants are often pulling 6, and sometimes up to 8 pounds dry… from a single plant! Of course, this involves expert plant training, gardening, not to mention the near perfect conditions that the Californian coast provides.

  137. If you are growing indoors in soil; Use a jiffey pellet to propagate your seed

    If you are setting up a hydro system, then use 1.5″ rockwool cube.

  138. I am new to this and plan to plant my first crop I have been reading a lot of information on growing and I have 1question be for I start germination what is the best way to germinate for indoor growth

  139. Not at all. I have to assume you are using 3 – 1000 watt lamps. Max. coverage for those lamps in general are 6’x8′, but overlapping the footprint would give you better results; As long as you can control the temperature.

  140. Nice video. Very informative. Ive been growing legal medicine for the last seven years. I recently was forced to switch to a 10x10x8 grow tent. Im currently running 3000 watt hps lamps with three plants per lamp that were veged for 5 weeks. Do you think 3000 watts is overkill?


  141. Your comment really made me laugh, because for some reason I couldn’t help imagining you as a seventeen year old pretending to be a senior to cover himself for self-incrimination or something.

    Read at face value, though, your comment also makes sense. So double thanks.

  142. Thanks for the heads-up on the maths. I like maths, but I forget to do them sometimes. That should be especially enjoyable for North American brethren, who don’t say maths very intuitively.

  143. To be fair, in English at least, bud prices are traditionally quoted in imperial; the ‘gramme’ is a more recent creature of retailing it at a very petty level; the customer’s choice is between a gramme or seven grammes, or quarter ounce, which might cost four or five times as much. It’s just a nice heritage thing for an enjoyable part of life; like twenty or sixteen ounce beer pints sit either side of the internationally most common 500mL.

    On the other hand, crystalline drugs seem to have been in metric for decades, even in the States. With cannabis for medical purposes, the more scientific-sounding 5g unit seems to be used in the US, just as 10g is used in Uruguay.

  144. Pete,

    I have not used the Earth Box. However; If you sign up to our Support forum, I am sure you will find many members with experience with that product.

  145. […] If you use the SCROG (Screen of Green) method you also have to prune your marijuana plants. Place a screen at 50 cm above your plants. Take the top out of every plant when it’s 10 centimeters from the screen and wait until the new tops grow through the screen. Wait until they grow 10 centimeters through the screen, gently bend them and connect them to the screen. Prune your marijuana plants after the first shoots have grown through the screen. Wait a few days and force them into flowering. During the first two weeks of the flowering phase your marijuana plants will keep growing. Check this article for maximum yields how much marijuana can one plant produce? […]

  146. Hey Dennis,

    Robert is always glad to help.

    As far as how many plants you should grow in your tent You did not mention what genetics you planned on growing. If I get your dimensions correct you have a 3’x3′ tent. I would go with no more than 4-6 for your 1st grow. It is better to have a little airy space and healthy plants, than it is to cram too many plants in a small space, causing environmental issues. As you become more experienced; You will be able to add more plants and incease your yields.

    I am on a fixed income. I know what it takes to put together a quality grow system on a small budget. For that reason, I recommend that you buy a 400/600 watt Ipower switchable digital ballast. LED is expensive, and the digital HID lamp is more versatile and provides more bang for the buck.

    It would be great if you joined our Support Forum. Look me up when you get there. Happy Groweing

  147. Hey Robert!
    Thank you for your emails…I’m gathering information to do my first grow…being on a fixed income I have to do it in steps. It is truly amazing how the marijuana helps me cut back on my pain killers I need to take to get by each day. My question today is about using LED lighting. Are they good for growing(read different thoughts from everyone. I have a grow tent that’s 9sq. ft. How much wattage will I need for the space, and how many plants should I start off with. Looking forward to not paying extreme prices, usually get real harsh commercial. It’s what I can afford since inmy area anything that is really good goes for around 20 bucks a gram. Thanks for your help!

  148. The whole world uses metric (not metrix) except you silly Brits and Americans, instead of rejecting it why not just learn it. You’ll see it’s much easier than the standard system, everything is in increments of 1s 10s and 100s. And everyone knows there’s 28grams in an ounce, just divide the total amount of grams given by 28 and you get your ounce equivalent, don’t see what’s so difficult about simple division. Great article btw Robert!!!

  149. Don’t hyperventilate over not getting the indoor quantities mentioned here. They are top end estimates if you are an expert grower and everything goes off without a hitch. These are yields to shoot for but not get all disappointed if you don’t achieve. Just enjoy the bud you grew.

    Something got lost in translation in that last section of the op. It only makes sense if you count 32oz in a pound, so cut those dry estimates in half. I guess the prices are per gram? Confusing. Overall good site, though. Keep up the good work.

  150. Hi rob,cheers for looking after us,I downloaded one of your book and it’s a pleasure,so keep up the good work

  151. Very great post. I simply sbtumled upon your blog and wanted to say that I’ve truly loved browsing your blog posts. After all I’ll be subscribing to your rss feed and I hope you write once more soon!

  152. Hey kbk420,

    Sorry my friend. This is a choice you have to make. It is a concerted opinion of most old school growers, that no matter what method you use, the yield will be close to the same, unless you really mess up one method more than the other.

    Best advice I can give you is to; Review the type strain you plant to grow. A “Sativa” may be better of being trained due to vigor and potential height; While an Indica, or Auto flower can be grown straight up, because generally, they grow shorter. Once you understand the potential grow characterisitcs of the genetics you are going to use; You will be closer to finding the answer to your question. Happy Growing 🙂

  153. Hello Greg,
    My opinion on LED lamps is: I do not use them. I use digital ballasts. I know growers i respect who love LED lamps and claim they grow just as much yield as HID lamps. I am not sold on this, without having done a side by side. If you join our support forum, you will run into some expert growers who can give you more insight. 🙂

  154. My grow space is 25” deep 88” wide 65” tall. Im getting 4 300 watt led grow lights. Completely white, great for reflection however I can not decide if I should grow five plants and train them or grow several smaller plants. I don’t want any of the light wasted so which is the better option Robert?

  155. Sometimes plants do not grow as tall under intense light. Buds get tighter though. Clay is generally full of nutrients and drains fairly well. You should be OK. Please join our support forum if you want faster responses, and more opinions from our expert growers.


  156. My first indoor grow I harvested a lil over an lb on 6 plants, for second run I used clones from exact same plants, but bought a water tester and was testing at over 800ppm! I spent $80 on a water filter that brought my ppm down to 14! My second grow yielded over 3 lbs dried just from giving them clean water. Also many things in hard water are also in your nutrients, and fertilizers, so in my case they were getting too much. Working on my first OD grow right now, started from seed, and build my own soil, trying different placement of plants, 4 in the ground but u dug out a 4’x4’x4′ whole for each plant and replaced it with my own soil. They look really good, just not growing as high as I’d expected. I put them in the ground about 6 weeks ago after they’re root ball was strong enough I felt for them to be left outside. They’re about 18″ tall after 6 weeks in the ground, is that normal? I might be over watering them, the soil that I didn’t replace is very full of clay, and drainage I’m worried about. I’m in CO, so we have high heat, and low humidity, too, how often should I be watering, and how much water for that size of hole? Great site, and great tips! Thanks!

  157. all of yall are lucky u are growing i have yet to even find a secret place to grow outdoors or indoors i am have 5 years in growing. my first indoor grow was a White Widow plant would like to order some of your special deals in seeds robert will let u know when i order

  158. led’s save power and have a very low heat output and you can grow some good smoke under them it just takes longer with them so in my grow i have a mix of m h lights and led ‘s and have great plants {50/50 each type} and it cut power use and heat output,my room with all led’s when finished is going to mixed lights

  159. I know CFLs are good for vegetative growth. And I keep hearing about MH and hps bulbs. But I’m looking into a fully assembled grow box for stealth and they have CFLs and LED lights. But I don’t see LEDs mentioned in anything else I’ve read. So any info on growing with those?

  160. I’m growing 4 plants that I will germinate under a 125 att cfl and transfer outside in 3 weeks. At week 8 ill transplant into 45 gallon buckets. They will be under constant direct light and the will get the proper amount of nutrients.

  161. How much can I expect from white widow if I have a 250w Hps and two 125 Cfl light on the sides of the plant?

  162. Hi Gary,

    With a 1000 watt light bulb you should be able to yield 2 pounds if the conditions are right. There must be a limiting factor. Is there enough CO2 in the air? Enough water and nutrients? What are the pH and TDS levels of the water? And what are the temperatures during the day and during the night? Maybe you can open a thread on the support page and tell us some more about your setup?


  163. been growing for 10 years , but still not getting yield u talk about , I use 1000w and ocean soil , veg to 3 ft tall 10 plants per light, yield is only 3/4 pound, not sure what is wrong but article did not offer much info on conditions in room and genetics

  164. Wow so comment didn’t work. 150 watt in a closet measuring 32 long 25 deep 60 high is this going to give me more then a couple ounces for one critical jack herer almost 2 weeks in the switch vegged for almost 3 months trying to get more then 2 ounces..

  165. I get 5 ounces or more on each of my plants I grow 16 in an iws flood and drain system under 4 X 600w lights in a tent that’s 2m X 2m X 3m. Veg for 8 weeks flower for 1 week. I haven’t tried the monster croping yet I might give it a go to increase my yield but my physco plants are quite bushy anyway.

  166. That’s ok buddy I use caterpiller sprays directly onto the buds nothing bad will happen. The clients can’t tell I used pesticides

  167. You guys are all dumb, I use a 400 watt hps , I yield anywhere from 8-12 ounces easily , veg for 6 weeks with 8 plants and you will have a pound in 4 months+drying+curing

  168. Thank you very much for all your help, Robert! This is my 3rd year growing outdoors, but this year I have more plants. (8) And they all seem to be growing at different paces, each one unique though from the same strain of seed. (Medijuana Feminized) Strange. And just as in the previous few years, I’m basically winging it. lol! But I have to say, WORM CASTINGS do wonders during the earlier stages. Is there anything wrong with using mainly worm castings & a little Miracle Grow watering from time-to-time until the flowering stage begins? Thanks

  169. What about if you use 8 VHO florescent lights, four blue and red. Will that increase the yield for growing indoor to the advertise yield? Yields only 1 to 3 oz. per plant is not acceptable in my opinion!

  170. Hey what’s up! Edwin Smith here I was wondering if you could answer some questions for me. I have a XXL13 Four-site current culture system with 600w KIND LED’s over each module. I want to main-line and FIM my plants in a 6.5×6.5×6.5 tent with a chiller and a active air temperature controller. I was wondering if there are any special nutrient mixes that you can let me in on so I can have an idea of some new techniques for my grow. Been doing this for about seven years now just want to get out of the normal. Can you help me just send me an email I know its hard to get to everyone. Let me know what’s up.

  171. hi great reading 4 a none reader just 1 ? when u r chatting about how much bud 1 would get per plant r u taking about the weight when 1st croped or when its dryed out thanks keep up the great work. budhunter

  172. Robert,
    I love reading about the potential these wonderful plants have. But it pains me that I’m not getting the results as such. I consider my self above a begginer but not yet an expert. Wondering if u can help me isolate the problem with my grow affecting my yeild. Thank you

  173. What about super cropping?

    One plant medical grow super cropped is better than scrog!
    Scrog maybe good for commercial growers however supper cropping is more efficient for personal growing for medical conditions!

  174. hi, I found your article very interesting. It did leave me with a question though. if we were to use a grow room of 3x3x6.5 feet with only 2 plants, would the wattage still make a difference in the amount of buds that would be produced? I guess what I am trying to ask is that if I am planting two plants, would 400 watts give it all the light that those two plants will be able to take or will having a 600 watt lighting system still be beneficial for a cultivation as small as 2 plants compared to a 400 watt lighting system?

  175. Is the sour diesel strand/ seeds good for a beginner grow ? And if not what do you suggest ? Don’t have much space.

  176. I have a 2 foot plant outdoors, i wont
    to know if I con start putin a lite on it at night to veg more

  177. Using Fluros or Energy saving bulbs for the veg stage and to propergate cuttings its ideal.. if u want big vigirous plants i suggest swapping over to a Hps Or Mh Bulb they have enuff grunt to penetrate the canopy and get some big colas growing.

  178. Hi Laura,

    I think your fluorescent lights can yield 50 to 100 grams at best. Fluorescent lights are perfect during the vegetative fase but not the best option for flowering. Instead of two 100watt fluorescent lights you can also use one 250watt HPS bulb. One 250 watt HPS bulb can yield a maximum of 250 grams.


  179. Hello

    I,ve been reading your articule and it is fantastic!
    i only have one question about the lights, due to the space i am able to fit for growing marijuana i can only use fluorescent bulbs. i just germinated 5 plants and i am using 2 bulbs of 105w each (in fluorescent light, wich would be like 420w of an incandescent bulb, so I asumed Im using 840watts of light). so the question is; how much gr per watt will the plant yield, using 840w in fluorescent bulbs?
    Thanks in advance!

  180. […] One method of reducing chemical contamination in the soil is by using a soil flush. This is generally not a recommended step to take, but it might be necessary in some situations. In reality, it should only be used as a last resort when trying to keep your marijuana plant alive. It essentially involves taking your entire plant with the pot included and placing it in a sink. From there, you turn the faucet on and let the water run through the soil so that it eliminates any of the contaminants that might have been harming the plant. The danger with this method is that you run the same risk of killing the plant by oversaturating the soil with water as you do by contaminating it with too many nutrients. But, sometimes this is the only way to ensure that the additives don’t kill your cannabis plants. […]

  181. Yes, I got them. Sent you back mine. Just don`t be scared 🙂

    I suppose, I would have many questions about your article. Waiting with impatience, because new plants are coming after about a week.

    Want to try implement what you are sharing .


  182. Hi Andy,

    There are no rules for the amount of plants etc. Did you get the pictures i sent you? Thats 5 plants in a 3 x 3 foot container. And because the plant doesn’t waste any energy on small, useless buds you get 5 to 10 huge ones per plant.

    I’ll keep you posted about the article


  183. It is amazing. I just wondering and can not understand, how you manage to get such big buds which are almost like the main . (actually hard to say where is the main and where is a branch)

    also three additional questions 🙂

    1) What is the distance between plants ?

    2) How many extra buds in average your plant has ?

    3) What is room size ?

    P.s will be impatiently waiting for “how to scrog” article 🙂


  184. Hi Andy,

    There are only 5 plants in pictures 7-9. All the branches that come through the screen are gently bend and tied to the screen with tie wraps. This is called the scrog (screen of green) method. I’ll write an article on how to scrog next week.


  185. epic article !!

    clear even to me 🙂

    just can not understand, what distance should be between plants?
    How many of them do you have on picture nr. 7 ?