How to Germinate Cannabis Seeds

Germination is the beginning of your cannabis seeds’ life and is easy to master. At this crucial stage, seeds grow and sprout into young seedlings. The best genetics deserve the best start, and all you need is two plates, some paper towel, and water. Apply the best germination method today and enjoy a great harvest.

1. Germination set-up

Prepare the first plate by lining the inside surface with two to three layers of damp paper towel. Drain excess water from your plate.

Place cannabis seeds on the top surface of the damp paper towel. Approximately three per plate; ensure they are not touching but are evenly spaced apart.

Add only a few layers of damp paper towel on top of the seeds, and let any excess water drain from the plate. Too much water lowers the chance of successful germination.

To complete the set-up, place the remaining plate upside-down and on top of the first plate, resembling pearls inside a clam.

2. Germination

Cannabis seeds need a dark, warm, and humid atmosphere to germinate.

Around 21°C (70°F) is perfect. Check the paper towels every second day and if required, spray with water to keep conditions moist for your seeds.

After a few days, tiny roots will begin to emerge. Congratulations! Your seeds have survived their first stage of life. Don’t worry if some of your seeds have not yet changed, they may just need a little more time as germination can take up to 14 days.

3. Plant the seedling

Once the roots are a few millimetres long, they are ready to be delicately transferred to a small container filled with your growing medium of choice (rockwool, coco-fibre, or soil).

Make a hole in the growing medium that is 2 – 5 mm deep. Use tweezers or your fingers to transfer germinated seeds gently into the hole (root pointing down) and lightly cover with a fine layer of your medium. Do not pat it down too hard. The stem and the first tiny set of leaves, called cotyledons or ‘seed leaves’, should begin to emerge 24 to 72 hours after the seeds are planted.

4. Supplying a light source  

Seedlings must be exposed to sunlight once they sprout. Ensure this is a gradual process as too much heat causes stress and will stunt growth.

Find a sunny place where you can begin to increase sun exposure, such as a windowsill. Ensure sun exposure is increased by an hour or so a day.

For an indoor plant you can use a fluorescent light (keep normal distance from bulb) or HID lighting (50-80 cm from the bulb).

Take care in the first week or two, as seedlings are still quite delicate and sensitive to the elements. They won’t need a lot of attention until the vegetative stage so avoid overhandling.

Germination is the beginning stage of the growing cycle, and this easy-to-follow guide gives your premium genetic cannabis seeds the best start to life. Whether you are a first-time home grower or a well-seasoned gardener, share your experience or any questions in the comments down below, as well as your tips and tricks!

  • Disclaimer:
    Laws and regulations regarding cannabis cultivation differ from country to country. Sensi Seeds therefore strongly advises you to check your local laws and regulations. Do not act in conflict with the law.

Comments

32 thoughts on “How to Germinate Cannabis Seeds”

  1. Hey there guys I’m quit new to this and just got my first seeds but it looks to me like the seed will not germinate because it floats in the water is this true ?

    1. Der Samen sollte nur zwischen feuchten papiertüchern liegen. Ertränken ist nicht bei allen Pflanzen gut.

  2. I never use paper towel or any other similar material for germination as they increase the ph of water dramaticly. Tap waters are around 7ph generally and will easily rise up to 9+ when poured on paper towel. I use rain water which is guranteed to be 6,5 ph most of the time. I spray some in a mini jar , put the seed in , spray some more, close the cover to keep moist in, put in a dark place and avoid disturbing by moving until the rootling grows 5mm at least. Water is a bit cooler than air so I prefer 22-24 degrees. Once they are in the soil and sprouted, some breeze parallel over the leaves is essential to stop fast streching and for a stronger body imho. If white light source is not close enough( up to 5 cm depending on lumens without extra heat), fast streching will still occur despite the breeze.

  3. Hi, Once seeds have sprouted, how long can or should you leave them to grow under 24 hr lights before moving to your outdoor garden?

    1. Mark - Sensi Seeds

      Good afternoon Ken,

      I hope you’re having a great day.
      For the vegetation process, a light schedule of 18 hours of light, and 6 hours of darkness is preferred. Many growers get plants acclimatized to outside by placing them in a window, or under direct sunlight for a few hours a day.

      Thanks again, and have a great day!

      Mark

      1. I’ve always wondered…with early seedlings, they respond best to a first week on a sunny windowsill, but then how can you give them the 18/6, given that the sun isn’t out for 18hrs?

      2. Tim - Sensi Seeds

        Good question. The hours of sun keep increasing in early spring to late spring. So everyday the plant will get more hours of daylight. This signals the plant that summer is coming. Just don’t start too early, though.

  4. Hello everyone, all these suggestions are wonderful but I think a lot of you make it sound a little overwhelmingly. I’ve been very successfully cultivating for decades and I’ve always just placed my seeds, be it 1 or 100, in between 2 folded sheets of tissue which I’ve made wet with tap water. I then place them on a tray or plate in a warm dark area , such as an airing cupboard and leave for how ever long they take usually, 12 to 24 hours. The ONLY thing I do which takes effort is PH balance the water I germinate them in and I’ve only lost 5 seeds in nearly 40 years .

    1. Mark - Sensi Seeds

      Good afternoon Paul,

      I hope you’re having a good day,
      Thanks for sharing your experiences with germination. pH balancing is a great tip 🙂 You also might be interested in our new Jamaican Pearl Feminized Grow Report

      Thanks again, and I hope you continue to enjoy the blog,

      Mark

  5. I lightly score my seeds by shaking them inside a rolled up piece of sandpaper – sandpaper side on the inside before leaving them in a cup of water for a few hours to hydrate. I then place them between wet (good quality) paper towel per instructions above. I find using an old plastic takeaway container with a heatmat below keeps the humidity high and with good end results.

    1. Mark - Sensi Seeds

      Good morning Jonny,

      Thanks for sharing your methods for germination with us, the heat mat and low-humidity are great tips!

      Thanks again, and I hope you continue to enjoy the blog,

      Mark

  6. I have found out that the best and fastest way is to take a glass of clean/filtered water and place the seed right on top of the water (floating – NOT immersed in it!). If the seed is viable it will sprout in no more than 48 hours. Right after that you plant it in your pot/soil etc and you’re done.

      1. Once you put the seeds in water they normally won’t sink straight away, leave it for around 5 hours and then tap your seeds and they all should start sinking if they don’t then they won’t work. But still leave them over night and tap again and take out the ones that didn’t sink and throw them away or plant if you want to try your luck.. take all the other seeds out and follow instructions above you’ll see the open within a day..

      1. No, don’t leave the seeds in water for longer than 24 hours or they will drown.. after around 12 hours all your seeds should have sunk if they haven’t then just give them a tap and they will sink.. then take them out and follow the paper towel and plates instructions

  7. Tammy Bowman

    Take aluminum foil flatten it out and put on top of your dirt it detects planes and grow it just like a tomato plant

    1. Mark - Sensi Seeds

      Good morning Tammy,

      Thanks for getting in touch with Sensi Seeds, and sharing your germination method with us!

      Thanks again, and I hope you continue to enjoy the blog.
      With best wishes,

      Mark

    2. Detects planes? Like magnetic? I’ve always has best success 24-48 hours soaked In water, spring water if possible. Usually do this in a shot glass, once they pop I’ll take a paper towel fold so it’s 2 layers then fold once more so you know where center is. Dump the seed in the middle of the edge and the true center (reason we folded a 2nd time)as well as the water just enough to saturate the paper towel. Do not soak! Carefully with the seed in the middle using sterile tweezers turn so the tap is growing down. This will prevent circling and tangling if doing multiple seeds. Now you can fold the other half so your seed will be “sandwiched” between 2 layers. At this time carefully take a corner and the waters attraction should keep your paper towel from unfolding but just in case be gentle. Holding it from 1 corner you can dangle it over a cub or the original shot glass so any extra water runs off. Now take a standard zip or press n seal sandwhich bag and slide your napkin in Carefully . REMEMBER which way was down! Work the air out making jt flat snd seal. Find a temperate dark area around 70°. A cabinet works we’ll as your going to prop it up with taproot facing downwards. Now just close it up and wait in 24-72 hours checking once a day. In rare cases you could have a 1/2″ tap root in the first 24 hrs some may take 4-5 days. Once the tap is about 1/2″-3/4″ long its ready for transplant into its first small pot. With this paper towel method I typically have 100% success.

  8. Hi guys

    Can you leave your seed to develop longer roots in the germination phase and can this make them better to grow or is a big no no?
    Last year, I had 2 seeds that had really long roots with lots of secondary roots coming out when they were planted, one of which died after a couple of weeks and the other grew into a huge plant.
    The other two seeds only had a short germinated growth and both died almost immediately after planting so not sure what I can learn from this…lol

    Appreciate any thoughts and advice

    Thx Christina

    1. Mark - Sensi Seeds

      Hey Christina,

      Unfortunately, legal restrictions mean we can’t answer grow-related questions or give grow advice on this blog. However, other readers of this blog will often answer questions like yours.

      Please check out the following articles on our blog which I think you may find of use, and I hope you continue to enjoy the blog!

      What are the best conditions for seedlings

      When can seedlings be put under lights or in the sun

      The Life cycle of Cannabis: from seed to harvest

      With best wishes,

      Mark

  9. How often do you water and how wet should the plant be? Please.
    Also if they are outdoor plants do you need to keep them covered with clingfilm for a wee while or do you just hope for the best. Thanks

      1. Just drop the seeds in water, they will sprout , don’t have to use a towel and check it all the time , drop it in the water , let it float then it will sink and the root will grow out ,let the root get 1/4 inch and plant it where it’s going to grow , 8 hours sunlight starting as soon as it is out of the soil. Always grows great , don’t have to transplant from cup to gallon to bigger and bigger , if it’s growing outside put it where it stays , always does just fine.

  10. marijuanatravels

    I recommend this article to all breeders and cultivators who plans to germinate seeds and to some who don’t know how to germinate seeds, this article has the best and perfect ways on how to do it.

  11. I have large bay windows at my condo which get about 11-12 hours of light per day. They are tinted but warm. I grow other indoor plants there perfectly. Is an ok place for my pot plants?

    1. Scarlet Palmer - Sensi Seeds

      Hi Ken,

      This sounds like a great place for all kinds of plants! I recommend you have a look at autoflowering varieties, as otherwise light pollution may negatively affect the flowering cycle. Good luck, and happy gardening!

      With best wishes,

      Scarlet

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