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Of all the elements that marijuana will need to be successful, light is by far the trickiest one to control. This is especially tricky with marijuana that is grown outdoors, as we cannot control the sunlight ourselves.

The best way to make sure your plants receive the proper amount of light at the correct times is to choose a great location in the beginning. Picking this site is something that can only be done successfully with a careful understanding of how light and other elements will affect your marijuana plant, and why they have these effects.

Tip: make sure to download my free Grow Bible for more information

The importance of sunlight

sunlight important for marijuana plants

Cannabis can grow to great heights if treated correctly. This usually involves plenty of sunlight, but it is also possible to grow it using just a skylight. This is possible because of the durability and hardiness of marijuana plants. The size of the plant and buds will be much less though.

So why is sunlight so important? It is essential for marijuana plants to produce their stems and leaves, which are important for taking in even more sunlight – and this helps them gain more energy that is used for further growth.

When you maximize your plants’ growth, you maximize your yield and quality of weed. There is no better way for your plants to grow than to make sure that it is receiving the proper amount of sunlight. Soil and water are also necessary, but they won’t make as much of a difference as sunlight will. The more sunlight, the higher the yield.

Contrary to what may seem logical, it is the darkness after daytime that starts up the flowering in cannabis plants. This, of course, is a crucial part of maximizing your weed yield. After a certain amount of consistent darkness, a mature plant will receive the message to start diverting its energy from being used for flowering instead of growing. For this reason, it’s important to start growing the marijuana plants as early as you can in the spring, so they can absorb the most sunlight and use the most of their life cycle for growing.

Choose a sunny growing site

sunny marijuana growsite

Because of this natural process, it’s important to choose a growing spot in a place where it can get the most sun exposure possible. The days are the longest during the middle of the growing season – the sun could shine for longer than 12 hours a day during this time of year.

You need to find a location that is free from objects or other plants that might block your plants from receiving the most amount of light possible. Never forget: your plants need as much sunlight as possible, so they grow as much as possible. Also read this article The Best Places To Grow Marijuana Outdoors

If you live in the northern hemisphere (United States, Canada Europe), the best location is most likely a spot that is facing the south. The opposite is true for people living in the southern hemisphere (Australia). Because of water access and concerns about security, however, this may not be doable for everyone.

How much darkness for outdoor plants

darkness outdoor marijuana plants

At the bare minimum, make sure your marijuana plants are receiving five hours of direct sunlight, as well as five additional hours of indirect sunlight. If you must make a decision of whether to use mainly morning sun or afternoon sun, it is generally  better to choose the morning sunlight, as it will stimulate growth more effectively.

If you live in the north, you will probably have some problems to deal with that southern growers will not. For instance, darkness makes a big difference in regions that are further north. During the growing season, nights are short. This means that cannabis might not get enough time to flower before the first fall frost occurs.

This doesn’t mean it’s impossible for northern growers to get a good yield from their crop. It simply means that they will probably need to simulate a longer night in order to get the plants to start flowering earlier. This is tricky because even the briefest amount of light will make plants start growing again and put off flowering. Therefore, it needs to be a complete, uninterrupted darkness.

The opposite problem occurs in the south, near the Equator: they have very long periods of darkness. Nighttime will last more than 10 hours. When this happens, marijuana plants can flower too early. While this is something that needs to be dealt with, it is much easier to give a plant more light than to try and reduce the amount of daytime it is exposed to.

In both cases, remember to look at a plant’s relationship with light in terms of its full life cycle. Light is integral to everything from germinating to growth, to flowering so it cannot be taken lightly. Because marijuana fares so well outdoors, it should be fairly simple once you’ve successfully gotten them started. All that is required is picking the perfect place to grow them, and then the changing amounts of sunlight and the turning seasons should take it from there.

How much sunlight for marijuana plants

how much sunlight outdoor marijuana plants

The final thing to consider is the amount of light your planting location is going to be exposed to. This isn’t to say its impossible to understand: you just need a place with as much sun exposure as possible. The more sun, the more successful your harvest will be.

People who don’t know what they are doing often choose to plant their cannabis plants in the middle of a forest. For people who have a good understanding of the importance of light to their harvest, this is clearly not the best choice. Your marijuana plants would need to fight for light, competing with tall, mature trees.

You need to find a place that gets not only morning sun, but also further sunlight as the day continues on. This can be the most challenging part of finding a location for your plants since areas that receive good lighting are also more noticeable or vulnerable to be discovered.

TIP: Looking to buy seeds? Visit the ILGM cannabis seed shop

Just remember that without a minimum of five hours of direct sunlight (and quite a bit more hours of indirect sunlight), you will not be happy with the result of your marijuana harvest. Find more than one site to plant your marijuana plants so you can figure out which one of these sites is best for cultivating cannabis of large sizes and quantities. It will also help you more efficiently care for your plants in the future since they will all be in one superior location.

All in all, do not rush through these important details about light for your cannabis. It is a steep learning curve and takes a lot of careful planning, but in the end you will be able to sit back, relax, and enjoy the result of all your hard work. It will definitely be worth the effort.

Thanks for reading. Please leave comments or questions below and don’t forget to download my free grow bible

Robert

The founder of I Love Growing Marijuana, Robert Bergman, is a marijuana growing expert that enjoys sharing his knowledge with the world. He combines years of experience, ranging from small-scale grows to massive operations, with a passion for growing. His articles include tutorials on growing... [read more]

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  1. By Keith

    ,16 May 2013
    Hi some great advice just waitin on my first seeds built a Polly tunnel and I was wondering can I start my plants indoors in a window with out lights to get it hardy before I put it out side […]Read More
    1. By Robert Bergman

      ,16 May 2013
      Hi Keith, Polly tunnels, great. You can get really good results with those. I always recommend to use a fluorescent light for your marijuana seedlings. You can control the temperature (20-25 C) and hours of light (18-24). In your window […]Read More
  2. By Jason Mercer

    ,07 Sep 2013
    Hey there Just a quick question. I grew outdoors this year my plants are around 8 ft tall in pots and budding good I made a 3ft by 3ft skylight in my shed and have 2 big doors on the […]Read More
  3. By mayaya

    ,24 Sep 2013
    Hi I've been growing plants outside in ireland and IRS been a great summer but now the weather is quite cold I'm wondering if I could take my plants indoors and leave them under a skylight? As they are in […]Read More
    1. By Gerry

      ,05 Aug 2016
      Eww…you don't want your crop to fail at this time…be careful at this time, because extra cold and moisture can easily develop mold on your buds in the fall. Mold on your buds is worse than waking up and having […]Read More
      1. By richard kirby

        ,09 Oct 2016
        to prevent white powdery mold use a little 3 percent hydrogine peroxide in ur water if u grow out in pots it kills all the harmful bacteria in ur soil as well as good I mix wiyh my nutes wen […]Read More
  4. By Jenna

    ,13 Aug 2014
    I've had plants growing outside in pots and they are about 5 ft tall and 12 weeks old. They look very healthy, but I'm concerned that I won't have enough time for flowering before it gets to cold because they […]Read More
    1. By sassykat

      ,17 Aug 2017
      I would like to know the same thing that Jenna is asking. I'm in mid-Michigan. I have my card. The date is August 17, 2017. My plants are beautiful and healthy but they aren't flowering yet. What do I need […]Read More
      1. By macmommy

        ,18 Aug 2017
        try a fertilizer that's high in phosphorus and potassium to stimulate flowering.
  5. By Best Outdoor Marijuana Seeds For Your Climate

    ,01 Sep 2015
    […] of growing. This can be used to the grower’s advantage. Some growers intentionally restrict the amount of light with the purpose of speeding up the flowering process. They might move potted cannabis plants, or […]
  6. By Watering Marijuana Plants Outdoors

    ,06 Oct 2015
    […] plants will need without first knowing more about some other factors such as soil, weather, the intensity of the sun, and exactly what time of year it is. You will even need to take into account what exactly the […]Read More
  7. By Male Or Female? How To Sex Outdoor Marijuana Plants

    ,23 Oct 2015
    […] number of plants has its benefits as well, since any plants that are still there will receive more sunlight and will allow you to focus your efforts on fewer plants, making your work more effective. Since […]
  8. By jay biggz

    ,20 Jan 2016
    thanks for the info it really helps me n i get to share this info with lots of ppl also
  9. By Russell Morley

    ,03 Mar 2016
    Thanks Robert for sending me my bible must be all about money
  10. By Mediterranean

    ,19 Apr 2016
    I live somewhere in the Mediterranean on top of a mountain,and am about to start my first ever grow outside so sunlight isn't much of a problem,could you give me any tips for growing in the med? I'm growing w […]Read More
  11. By latewood.ILGM

    ,21 Apr 2016
    Mediterranean , IN the "Med" and on a mountain. That presents a lot of variables. My advice to you is to research the grow methods of local fruit and vegetable farmers. This will give you a sound base on which […]Read More
  12. By Marcus

    ,03 May 2016
    This my first time growing anything and I only use the seeds from batch buds I've smoked they seem to be growing okay but I want to know is it okay to start growing outside and then bring them indoors
  13. By latewood.ILGM

    ,04 May 2016
    It is much safer to start plants indoors and control environment It is highly uncommon to start plants outdoors with the plan to bring them indoors to mature and finish.
  14. By Madman

    ,07 May 2016
    I started female clones in December, indoors. They moved outside in early April and are now flowering like mad. Is it too soon? Will the long days cause them to go to veg.state again? They are all 3-4 ft tall […]Read More
  15. By Royce

    ,10 May 2016
    Is June 1st safe to turn off the lights and still have enough natural sunlight, for the plants not to flower? I'm in northern California. Any advice would be very helpful. Thanks R
    1. By latewood.ILGM

      ,10 May 2016
      Ropyce, In June we have the Summer Solstice. Days start getting shorter each day after that. You might want to join our support forum, and download our free grow bible to giver you more confidence
  16. By latewood.ILGM

    ,10 May 2016
    Madman Generally plants finish in 4-5 months. You in month 5; What do you think? There is nothing you can do now; You are committed. The days should not get too long to revert your plants. However; There are no […]Read More
  17. By Maylina

    ,21 Jun 2016
    Hi, I live in Georgia.I have my plants outside.I get plenty of sunlight,but was wondering about the night.I have an outdoor light and where I have my plant,the light hits it.Is that going to mess anything up?Do I have to […]Read More
    1. By Gerry

      ,05 Aug 2016
      I'd only be concerned about that pesty night light once you start flowering. While it's in vegetative state, a light at night like that will do no harm…although, once you start cutting the light/dark schedule to 12 & 12 hours […]Read More
    2. By Jeff

      ,13 Aug 2018
      Yes it will mess it up shiled it
  18. By Lion

    ,02 Jul 2016
    can solar balcony lights affect the growing and flowering process?
  19. By Robert

    ,20 Aug 2016
    I started many years ago and decided to get back into it about 3 years ago. Had trouble finding good seeds so I took a chance and ordered from ILGM. I am in Florida and I have had good results […]Read More
    1. By Roy ILGM

      ,22 Aug 2016
      Ah the Northern Lights, yes they're beautiful! Great to hear your results Robert!
  20. By omer shaul

    ,10 Sep 2016
    dude pls, weed needs sunlight but not as much as possible, u make people do mistakes, cannabis needs a gentle caring.
  21. By John

    ,22 Dec 2016
    Great read thankyou Marcus much enjoyed
  22. By Marcie Myers

    ,28 Mar 2017
    Enjoying the read as I begin with my feminized seeds. One question which may be in another area but if you start you plants outdoors early, maximize as instructed, WHEN do you begin to put them in 12 hours of […]Read More
    1. By latewood_ILGM

      ,28 Mar 2017
      Marcie Myers, Outdoors you do not control the photo period. 12 occurs approximately at the Summer Solstice in June. I live in the Hell Hole Swamp. :) Go Tigers. I recommend you join our support forum. We will be glad […]Read More
    2. By Amy

      ,11 Jun 2017
      The longest day of the year is summer solstice, the 21st of June in the northern hemisphere, and 21st of December in the southern hemisphere, and the further away from the equator you are, the longer that day will be. […]Read More
    3. By greenthumbjambam

      ,25 Jun 2018
      now if you was indoors any where from 90-120 days you can start cutting light just as long as they are strong enough to hold the weight
  23. By Jackie

    ,06 May 2017
    I love this site! I have my first grow from seeds (Wonder Woman) going now in about the 5th week of veg. I've learned so much from this site and Robert's grow bible. I started my seeds in seedling soil […]Read More
    1. By Roy ILGM

      ,08 May 2017
      great troubleshooting there Jackie! – I❤️GM
  24. By Sandra

    ,06 Jul 2017
    I have been growing my babies since February, I have moved them outside in 5 gallon buckets. They get morning and evening sun with shade throughout the day. When can I expect to see buds?
    1. By latewood.ILGM

      ,11 Jul 2017
      Sandra, I am surprised you are not seeing buds. If I read your post correctly, you are 5 months growing... May I invite you to join our forum ar ilovegrowingmarijuana.com and I, among other friendly growers will help you figure […]Read More
  25. By Oldtimer

    ,09 Jul 2017
    Sandra my kush ladies were transplanted in late April/early May into the ground and also 10 gal containers. Theey are now 4 ft up to 5 ft now in height and width in a So Cal (33 Latitude) climate. To […]Read More
    1. By latewood.ILGM

      ,11 Jul 2017
      Hey Oldtimer, Thanks for sharing. :)
  26. By Ben H.

    ,19 Aug 2017
    What can I do if my outdoor plants don't get enough sunlight throughout the day? I thought they would receive enough but they are growing very slowly and it's getting towards the end of the season. They are grown organically […]Read More
  27. By Ben H.

    ,19 Aug 2017
    They were transplanted into 45gal fabric pots around the end of July and they were already 2-3 weeks old. They are around 7-8 weeks old now.
    1. By latewood_ILGM

      ,28 Aug 2017
      BEN H., I suggest you join us at ilovegrowingmarijuana.com for a better discussion of your issues. The blog here is not set up for the lengthy support you need to get going. All I can say from what little info […]Read More
  28. By Sonya

    ,15 Sep 2017
    Well this is probably the 10th year we've tried growing our own pot (every other year as soon as the plants start budding someone stole them right from the back yard) we currently have 2 very large plants outback with […]Read More
    1. By latewood_ILGM

      ,20 Sep 2017
      Sonya, I can only advise you to join our forum, where we can all share the necessary info to get you an informed answer. ilovegrowingmarijuana.com
  29. By chad

    ,11 Nov 2017
    i live in N/W Australia where the weather is very hot,how do i stop my plants going into the budding stage when my plants are still very early in growing stage.sunlight isn't a problem.cheers
    1. By latewood_ILGM

      ,17 Nov 2017
      chad, To keep plants from budding; You need to limit the dark period to 10 hours or less per 24 hour period.
  30. By waylon

    ,13 Nov 2017
    hi im just trying couple clones outdoor they are starting to flower way to early so i prob did the wrong thing but i trimmed the tops as i did not do this in vegeing as i have only really […]Read More
    1. By latewood_ILGM

      ,17 Nov 2017
      Waylon, Topping plants in flower creates a stress and can cause hermaphroditic traits to show. Plants should only be topped in the vegetative cycle. Cannabis is a very adaptive species. Only time will give you the answer to your question, […]Read More
  31. By Gary

    ,05 Jun 2018
    I have a some plants in pots is it best to put in greenhouse or the ground . Also when we go away what is best way to water them as I have no to water them.
    1. By latewood_ILGM

      ,13 Jun 2018
      Gary, Where you place your plants is a decision you need to make in order to follow the grow plan that you come up with. I suggest nice cloth containers in a greenhouse but, if you take all the necessary […]Read More
  32. By billy

    ,07 Jun 2018
    OK - I live in Cambodia and am thinking of an outdoor crop. Done plenty indoors but this is all new to me. We have 12 hours light and 12 hours dark - ALL YEAR ROUND. I was thinking of […]Read More
    1. By latewood_ILGM

      ,13 Jun 2018
      billy, I would go with feminized Sativa strains because Sativa is also derived from genetics in equatorial regions such as yours. Good Luck and Happy growing
  33. By greenthumbjambam

    ,25 Jun 2018
    personally i have actually found out that after harvest you can leave the root ball attached and leave a few bottom limbs on as well. spread the roots and repot move inside and go to a 24 hr light cycle […]Read More
    1. By latewood_ILGM

      ,21 Aug 2018
      greenthumbjambam, You are talking about re-vegging. The only part you got off on was using a 24/0 photo period. Never use 24/0. Maximum photo period should be no longer than 18/6, and some would stretch that to 10/4 for vegging […]Read More
  34. By Caledonia

    ,14 Aug 2018
    I live at latitude 55n and my plants still her to g too much light n it's mid August a few white pistils but no buds any suggestions?
    1. By Caledonia

      ,14 Aug 2018
      Getting too much light sorry
    2. By latewood_ILGM

      ,21 Aug 2018
      Caledonia, Not sure of your location. Naming it would help others know where in the world you are talking about. :) Without knowing how long your photo period is; I cannot really advise you. If you ahve a few pitils […]Read More
  35. By jermaine

    ,13 Sep 2018
    Hi there I have a seedling with 3 sets of leafs already Iit started spring here in south Africa What I want to know is I'm keeping my seedling in a white cupboard under two lights which makes a 26w […]Read More
    1. By latewood_ILGM

      ,04 Oct 2018
      jermaine, You need air circulation or you promote mold and other environmental issues. Join our forum and get tips from our friendly members and expert staff. :)
  36. By Angela

    ,23 Apr 2019
    Very well written and Easy to understand. thank you! not everyone can explain the right ways to garden.
  37. By dennis

    ,23 May 2019
    i had a great harvest last year with the seeds i purchased. learned so much from your website. looking forward to another great year.
  38. By David

    ,04 Jun 2019
    I live In norhtern Nevada and indirect sunlight is my biggest problem cause their is no shade unless I build it and then it causes problems I have the best access to sunlight but is there a things as to […]Read More
  39. By Rob

    ,11 Jun 2019
    Huge note is that if you are nOt planting directly in the ground you will need to make sure that your pots/bags are not gett too hot. 18° celsius for my opinion is max temperAture for the soil and Roots […]Read More
  40. By Robert

    ,03 Jul 2019
    I found this very helpful thanks
  41. By Robert

    ,03 Jul 2019
    If I grow my plants in a pot outdoors how big of a pot do I need to plant them in
  42. By Johnathan

    ,12 Aug 2019
    Does it matter if my plants are only 3 week old and they’re recieving sun light all day? Would it burn my plant I live in puerto rico ( tropical weather)
  43. By Sage

    ,31 Aug 2019
    I've Grew for 30 years back in TN. I've been in the PNW for over 2 years now and this is the 1st outdoor grow out here. The sun is making my plants droopy when exposed to direct sunlight. The […]Read More
  44. By Terri

    ,03 Sep 2019
    Ok is 11 to 12 Direct sunlight no shade at all ok

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