One of the most popular questions regarding marijuana is “How much marijuana can one plant produce?” or “How much will a 600 watt HPS yield?” There are no simple answers to this question as each situation depends on a number of variables.

Many people take up growing weed and they have a variety of reasons for doing so. In every case, you want to get the most out of your crop. Whether you’re growing for medical reasons or you just want to make a little money on the side, the overall yield is a top priority for all growers.

In this article I will discuss all everything there is to know about marijuana yields. Got questions or tips? Place them in the comments below this article.

Don’t want to read? Watch the video!

Maximum yield per plant indoors

Lights are of the utmost importance when you’re growing indoors. Experienced growers can produce about a gram of marijuana per watt of light (1 gram = 0,035 oz). So, a 400-watt HPS grow light can potentially translate to 400 grams or 14 oz of dried, usable cannabis.

Likewise, a grow room with 1200 watts of light can yield 1.2 kilograms or 42 oz of cannabis. Having the right equipment, adequate nutrient solutions, beneficial air quality, and other valuable factors is important for producing the highest yields possible. Making sure the plants have space to grow is also key.

Tip: make sure to download my free Grow Bible and learn how to maximize your yield

Average expected yield per plant indoor from soil

If you are using soil to grow indoors, you can expect somewhat less of a yield than if you’d grown hydroponically. This is because hydro growers can fully control the amount of nutrients their plants receive.

Check out these pics below. You can see that hydro plants grow faster than soil plants
Pictures powered by:Bergmanslab.com

Although soil growing can potentially lower your yield, it also is easier to grow. This is because it not only creates a buffer for error but it also holds nutrients within the soil. When growing in soil, there is room to make mistakes with pH and TDS and pay for it in yield. In terms of numbers, expect a maximum of 1 gram per watt. That means a 600watt lamp can produce 600 grams of marijuana or 21 ounces.

Average expected yield per plant indoor from hydro

Growing hydroponically yields up to 20% more, as long as you do not make any mistakes. With hydro 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 not soil) and incorrect levels can immediately effect the plants.

Check out these pics below. You can see that hydro roots grow faster than soil roots
Pictures powered by:Bergmanslab.com

There are rarely small mistakes while growing hydroponically. Even the most minor error can ruin your yield. However, those who do it correctly will be rewarded. You can expect up to 1.2 gram per watt, which means a 600watt HPS lamp can give you 720 grams of marijuana or over 25 ounces.

Cannabis plant yield calculator

A simple way to calculate your yield is by using a cannabis plant yield calculator. Yield O Rama has an excellent one that lets you select the type of light you’re using, the light intensity (lumen), your level of growing experience and your growing medium.

When using the yield calculator, keep in mind that an HPS grow light produces around 150 lumens per watt. For the exact amount of lumen that your bulb produces, check with the manufacturer.

The calculator has a few limitations- you cannot adjust it for the strain, and it’s only for indoor grows, but it is still quite handy. Check out the cannabis yield calculator here.

Marijuana yields in imperial measurements

• An average of around 1.5 to 2.0 oz  (3.5 oz for advanced growers) with 200-watt CFL lamps in a grow cabinet that measures 3.5 x 1.5 x 6.5 ft.
• An average of around 3.0 to 5.0 oz  (9.0 oz for advanced growers) with a 250-watt HPS lamp in a grow cabinet that measures 3.5 x 1.5 x 6.5 ft.
• An average of around 4.5 to 9.0 oz (14 oz for advanced growers) with a 400-watt HPS lamp in a grow room that measures 3.5 x 3.5 x 7 ft.
• 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.
• An average of around 9.0 to 18 oz (36 for advanced growers) with a 1000-watt HPS lamp in a grow room that measures 5 x 5 x 8 ft.

Marijuana yields in metric measurements

• An average of around 40 to 60 grams  (100 for advanced growers) with 200-watt CFL lamps in a grow cabinet that measures 1 x 0.5 x 2 m
• An average of around 80 to 150 grams (250 for advanced growers) with a 250-watt HPS lamp in a grow cabinet that measures 1 x 0.5 x 2 m
• An average of around 100 to 250 grams (400 for advanced growers) with a 400-watt HPS lamp in a grow room that measures 1 x 1 x 2.5 m,
• An average of around 150 to 300 grams (600 for advanced growers) with a 600-watt HPS lamp in a grow room that measures 1.2 x 1.2 x 2.5 m.
• An average of around 250 to 500 grams (1000 for advanced growers) with a 1000-watt HPS lamp in a grow room that measures 1.5 x 1.5 x 2.5 m.

How much does one marijuana plant produce

Indoor growth doesn’t bring with it a lot of certainty in terms of yield per plant. If you have only four plants per lamp, then you’ll yield much more than you would with total of sixteen plants for every lamp.

Tip: make sure to download my free Grow Bible  for more information about setting up your grow room

You should consider these things prior to choosing how many plants you want to grow:

• If you’ve only got 4 plants, your yield will be 25% less if one gets a disease or dies
• Vegetative growth lasts longer with only four plants. You should want to force flowering when the tips of the leaves are touching. If there are more plants, the leaves touch quicker
• Four plants are easier to manage than sixteen
• If someone catches you, you only have four plants to your name

Either way, growing four plants using a 600-watt HPS lamp could yield about 150 grams or 5.0 oz per plant. Sixteen plants that are grown under a 600-watt HPS lamp could produce about 37.5 grams or 1.3 oz of marijuana per plant. And if you only grow one huge plant per  600 watt HPS it could produce a pound of marijuana per plant!

Screen of green yield per plant

The Screen of Green (SCROG) technique is an excellent way to increase your yield. The idea is to top your plants and place a screen at 15 inches above your plants. When a branch grows 4 inches through the filter, tie it to the screen horizontally. Continue attaching the branches until you get a nice ‘blanket’ of tops. Before you continue reading, check these beautiful scrog pics from my marijuana education center, bergmans lab.

Here are three reasons why growing with a screen of green technique increases your yield:

1. No wasted light
Any light that hits the floor or walls is wasted energy. With the SCROG method, you create a thick ‘blanket of leaves’ out of your plant that prevents light from being wasted, and instead forces it to be absorbed by the leaves.

2. All plants are the same height
When every plant is the same height, each will receive the maximum amount of light. With this method, there are no plants or branches in the shade, and you can place the lamp as low as possible, as long as temperatures don’t exceed 77 Fahrenheit.

3. No fluffy or soft buds
Because you prune the bottom branches that don’t grow through the screen, the plant doesn’t waste any energy on developing the small, soft buds at the base of your plant. (FYI, they never ripen.) Your plants also don’t waste energy on leaves and branches it doesn’t need. All of its energy goes to the top colas!

I’ve used the screen of green method for many grows and I’ve always been satisfied with the results. If you use it, your yield can increase by 10 to 20%. You’ll need to master the basic grow skills of watering and pruning, however.

1000 watt HPS yield

Does a 1000-watt HPS yield more than a 600-watt HPS? Well, not necessarily. While a 1000-watt HPS bulb produces much more light than a 600-watt bulb, a plant cannot convert all that light into energy. It will need more CO2.

There is around 350-400 ppm of CO2 in the air. Indoor marijuana plants will use this CO2, combined with energy from the light to create sugars. If you grow in a closed grow room without an air inlet, the plants will use half of this CO2 within an hour and then slow down sugar production because CO2 levels are dangerously low. This is the reason why you have to ventilate your grow room continuously with fresh, CO2 rich air from outside.

Tip: make sure to download my free Grow Bible and learn how to increase your yield with CO2

With 350 to 400 ppm of CO2 in the air, your marijuana plants cannot create more sugars than the light from a 600-watt HPS bulb produces. So your yield will not be higher if you use a 1000watt HPS lamp under normal circumstances.

On the other hand, if you increase the CO2 levels, your plants will need more light, and in that case, a 1000-watt bulb can almost double your yield. It’s a large investment to buy the right equipment, but a 1000-watt grow light is worth it in terms of yield. Here is an interesting article about CO2 and tomato plants.

LED grow yield

There has been much said about LED lights, with many manufacturers claiming super high yields, but I haven’t seen them yet. I’ve tried a 300-watt LED grow two years ago and generated less than half of what I usually produce. Many of my friends also haven’t received desired results.

An interesting fact is that commercial tomato growers haven’t switched to LED. For me, that’s a sign that they’re no better or more economical than HPS grow lights. With LED, the light intensity isn’t as strong as with HPS lights. Instead, the spectrum is more important. Read the science behind LED on wikipedia.com

So, I can’t tell you how much you will yield with a LED grow light. If anybody has some results, please share them in the comments. I can confirm that LED lights produce a lot less heat compared to HPS lights. This will cause the plant to evaporate less water, changing the water and nutrient requirements for growers.

How much does a marijuana plant cost?

A store-bought marijuana plant will cost around $10 to $15. It will be a clone of around 5 inches tall, and they’re only available in the states that have legalized marijuana. High-quality marijuana seeds cost between $8,- and $15,-. Available all over the internet and of course in my webshop 😉

But these figures do not cover the cost of producing weed. You need to buy equipment, nutrients and keep an eye on the electricity and water costs. Here are some estimates, check my article about costs and revenues for more details.

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.

Growing 5 marijuana plants in a 4x4foot grow tent with a 600watt HPS light will cost you around $2000 per year and produce 1 pound of marijuana per harvest. With 4 harvests per year, each marijuana plant will cost around $100.

The basic equipment like filters, timers, and exhaust fans are very expensive. The price difference between a setup for 2 or 4 lights is only 20% higher, but the yield doubles. Read my article on revenues and costs of growing marijuana for more information.

How to yield a pound per plant indoors

It is actually not very hard to yield a pound per plant indoors. It only takes a lot of time and a lot of space. Want to feature your 1-pounder indoor plant on our blog? Send me a picture!

If you want to grow a one pound marijuana plant you need a 4 x 4 foot grow tent or other similar sized space, and a 600 – watt HPS grow light. Under ideal circumstances, a 600watt light can produce well over a pound of cannabis. If you limit your grow to just one plant, it can produce over a pound of weed. The picture below shows one plant under 600watt.

You have to prune and trim your plant a lot otherwise it will grow through the ceiling. Scrogging is the way to go to cover 10 square feet with one plant. Read my article How to scrog for more information.

Growing a one-pounder is a fun project, but there are some downsides. You need to veg the plant for very long until the entire floor is covered with leaves, so no light goes to waste. Plus, if your plant gets sick or anything, you don’t have replacements. But it can be done! If you pull it off, show me the results!

How much marijuana does one outdoor plant yield

Under perfect conditions, you can expect yields to extend to 500 grams or 17.5 oz of marijuana per plant. Space is a necessity (at least two meters) along with water, nutrients, and a dearth of pests and diseases. If you use containers, they should be at least 50 liters or 15 gallons in size.

It’s a good idea to germinate the seeds early on to allow the plants time to grow large. It’s best to germinate indoors where you can manage the humidity and the temperature for the seedlings. Again, 500 grams (17.5 oz) per plant is possible if everything goes as planned.

Aside from an adequate amount of sun, water, and nutrient quality, the actual genetics of the plant play a very important role. Seeds are vital and you need to have some exceptional seeds at your disposal. You can look through our cannabis seed shop to find the a strain that’s right for you. It all starts with genetics….

The difference in weight of wet and dry weed

Drying your weed slowly (10 to 14 days) in a climate controlled dark and dry place with a temperature of around 64 degrees will get you more weed in weight.

You will get about 20 % to 25 % out of your wet weed after drying, depending on the strain, the density of the buds and the way of drying. Only weigh the wet buds and not the whole plant.

Out of a well cultivated Sativa you will get approximately 20% -22% dry weed and from an Indica about 22% -25%. So out of one pound wet Amnesia Haze you will get approximately 7.4 ounces and if you dry one pound of White Widow you’ll get about 8.4 ounces. At a street price of $ 7 (Oregon) or $12 (Texas) this is very good profit.

You will end up with approximately 12.5% if you weigh the entire plant, including stems and leaves, while it’s wet

Thanks for reading and please feel free to share or comment on this article. If you order seeds from my seedshop you get full grow support and my personal email address. So if you encounter any problems during your grow process you can always contact me.

Robert Bergman