Here's a complete guide to autoflowering marijuana seed germination. Learn everything there is to know about how to germinate autoflowers! Growing your own autoflowering cannabis is easy, cost-efficient, and produces fast results. As you can see, sprouting autoflowering seeds is easy and produces rapid results. A step-by-step guide describing the best way to germinate your cannabis seeds. This germination method is ideal for the indoor and outdoor grower.
Autoflower Seed Germination Guide
Autoflowering cannabis seeds are just like any regular ones and the process of germination is the same, in fact, the only differences are in the way you treat you seedling when it has sprouted. Some growers say that autoflower seeds can be germinated in colder temperatures but I have not tested this hypothesis myself and have not seen side by side tests that show temperature differences and autoflower seed germination rates.
There are basically two methods of germinating autoflower seeds and they are natural seed germination and germination without growing medium. In nature autoflowering cannabis seeds usually drop down in the autumn, then they survive the winter and in the spring when the temperature reaches optimal level and the surrounding area gets moist they start to germinate. Autoflowering seeds don’t like overly wet conditions and if the seeds drop into a puddle or any other water reservoir or even a swamp then they usually start rotting and die. Looking from the other extreme when a cannabis seeds germinate it looks for a wet environment and if the tap root encounters a dry environment it shivers and dies. From the environments that these seeds encounter in nature we can see that they need to be really strong to survive different conditions and that is why autoflower growers in perfect conditions can achieve more than 99% seed germination.
Autoflower marijuana seeds can germinate in a wide range of temperatures. The optimal temperature for the surrounding air is 27 degrees Celsius but a bit of variation won’t harm the germination rate.
The soil temperature should be a bit lower and it should be around the 25 C mark, but again a little variation won’t affect the germination process that much.
If you are in a colder environment you need to get a heating pad that can heat up your growing medium and if you are in a hot environment get some fans or install an air conditioning unit.
More about autoflower temperature you can find in my previous post!
Autoflowering germination process requires a certain amount of water and water is the life-juice of the seedling that encourages it to start the growing process. Cannabis seeds require clear water, they can be germinated in tap water but you should check the PH level of it because it should be in the 5.6 – 6.2 range, but you can also use distilled water.
You should definitely avoid any nutrients at the germination process and first weeks of growth because the little seedling has a certain amount of nutrients inside the seed, and too many nutrients can halt its growth.
Growing medium preparation
Before putting your seed inside a growing medium you should fully wet that medium by flushing and only after it has dried up a bit you can put the seed in it. Almost any growing medium will be suitable for autoflower seed germination and you just need to check if the PH level is not too high or too low.
After the seed is put inside that growing medium, keep it damp but not too wet as the too humid environment can cause bacteria to spread rapidly causing the new seedling to rot away.
Natural autoflower seed germination
Just take your autoflower cannabis seed and put it in a wet growing medium 2 to 3 times as deep as the width of the seed. That little plant will shoot its tap root down into the ground and with those seed leaves will try to find the light.
Because the seed leaves are growing as they search for the light they will sprout into the air and the little seedling will be firmly held into its place by the taproot. If you plant your autoflowering seeds any deeper the seedling will struggle to push itself towards the light but if you plant it right at the surface the root can get in the light that can stun the plant’s growth.
This is the easiest germination method and this is how nature intended the seeds to be germinated, so you can pretty easily germinate seeds this way and they will pop 90 to 99% of the time depending on the seed quality and age.
Some growers prefer to put the seed in water for 24 hours before planting it in the ground but that does not increase the germination rate for young seeds and usually is done for older seeds.
This method is easy and if you don’t put those automatic seeds into the water for soaking then you just need to dig a small hole and put that seed inside.
This method is the least stressful for the little seedling as you don’t move it around and the soil acts as a buffer if there are any temperature or light fluctuations.
One of the disadvantages is that you cannot control every aspect of this germination process and you can’t know which seeds will germinate and which won’t.
This not knowing also creates a need for more pots and ultimately can cost you money because some seeds will not germinate and you can’t tell which will, but you need to plant each of them inside a different container.
Autoflowers are no good for transplanting and if you want to grow your plants into 5-gallon pots then you need to put each seed inside the end pot/rock wool cube and if some of them don’t germinate you have wasted your resources.
Autoflower starting without growing medium
This is a common method between experienced growers as it gives them full control of the germination process but in a sense is a bit more difficult. This germination method has a number of variations but the most common is the method of putting autoflower seeds in a wet paper towel in an almost closed environment.
If you are using this method you need to control your humidity and it should be at the 80 % level. You also need to control the temperature of the surrounding air because there is no buffer (soil/rockwool) that can protect the seed.
You also need to put your seed germination tray in a dark room and twice a day check if the paper towel has not dried yet. I will give an autoflower germination guide (wet paper towel method) at the end of this article.
Growers can see which seeds will germinate and put only those seeds in their containers not wasting any materials.
By germinating autoflower seeds in this manner you also have full control over the germination process and you can give the seed perfect condition for germination.
Seeds will also pop faster than if they were grown right in the growing medium!
Inexperienced growers can damage seeds while handling them to their growing medium or just getting some of the environmental variables wrong.
If they are left in the paper towel too long the growth can be stunned and they can even die.
This method requires a lot more work than just putting seed into the ground. Basically there are more things that can go wrong.
How to germinate old seeds?
Old seeds are those cannabis seeds that have been produced some 3 and more years ago but that doesn’t mean that you can’t germinate them.
Usually, seeds stay valid for 3 to 5 years if stored properly but with every passing year the seed germination percentage drops and it is harder and harder for you to germinate them. In time the seedling inside the seed loses its moisture and starts to shrink getting weaker and weaker up to the point that it is no longer alive and no moisture levels can’t bring it back to life.
The process of germinating old autoflower seeds is similar to regular seed germination, but you need to let them soak in water for a while so that the seed shell can soften and moisture can get inside the seed giving energy to cells to crack that shell and push out the tap root.
In the picture below you can see seeds in water soaking up that moisture. One of these seeds has drowned and two are floating on the top.
Usually, seeds will drown in a couple of hours and if they don’t drown in a day or two then they could be damaged. This drowning indicator is not as viable because the water surface pressure will hold even the healthiest seeds floating so you can gently push them down and if they don’t sink then, the seeds are probably damaged.
Autoflower growers usually let old seeds stay in water for 24 hours before putting them inside a growing medium or putting them in a paper towel, but be careful as leaving them in the water there for longer can harm them!
While germinating seeds you can easily stress them so you need to look out for the environmental stresses that can damage your seed germination rate.
The first thing is the light cycle fluctuations and the light itself. When germinating autoflower seeds they should be in complete darkness and no light should be shining on those newly sprouted tap roots, as it happens in the ground where there is complete darkness. After the seedling has sprouted you should not change the light schedules and let those newly grown plants grow in perfect conditions.
The second stress that those seeds should not encounter is temperature fluctuations as they can also damage the germination rate, in the ideal conditions temperature should stay the same all the way till the autoflower seed has sprouted and won’t dip in the night time or rise in the daytime.
The last stress that can damage the newly sprouted tap root or seedling itself is nutrients. For the first days and weeks of cannabis growth, you need to supply only pure water with no salts and nutrients.
Method for fixing seeds that are not sprouting:
If you tried to germinate your seeds and some of them did not crack open after 5 days or more you have one last hope and it is to gently try to crack open the seed shell hoping not to damage the seedling if it is still alive.
This method is not going to work 100% of the time and in most cases, you won’t get even 50% success rates but you can apply this method as the last resort if that seed doesn’t sprout naturally.
You can do this in a number of ways and the most common are:
Try to crack it open between your teeth, by lightly crushing one end till the seed shell breaks.
Another method is to do this with tweezers trying to get an opening at one end
The last method is just taking a small knife or scalpel and cutting around the seed till the seed shell breaks off, but you should be very careful not to damage the seedling if it is still alive.
Autoflower seed germination guide
First of all select a viable cannabis seeds that you will be germinating. You need dark-colored seeds that are strong and not too old. If you bought your autoflower seeds from a seed company then you probably should not worry about the quality of them as usually seed companies sell only the best quality seeds.
After selecting the best autoflowering seeds you have two options: putting them right in soil or germinating on wet paper towels. In this guide, I will show the second method.
You will need a container, clear water, and paper towels. For this autoflower seed germination guide, I chose to document one of my micro grows with a yogurt container as a pot, but the principles are all the same for any grow and the basic germination methods stay the same!
The seeds I used were Sweet Seeds – Fast Bud #2, the soil was a basic potting soil with balanced N-P-K and I used tap water.
First of all, you need to germinate your selected autoflower seeds!
How to Sprout Feminized Autoflower Cannabis Seeds
Growing your own autoflowering cannabis is easy, cost-efficient, and produces fast results. This makes growing autoflowering cannabis a great option for beginners and veteran growers alike. In this article, we discuss the first, crucial stage of growing autoflowering cannabis seeds germination and overview several easy, simple ways to sprout your autoflowering cannabis seeds. As you’ll see, germinating autoflowering cannabis requires little effort and can be achieved in just a matter of days.
Different Methods for Sprouting Autoflowering Cannabis Seeds
Another advantage of growing autoflowering cannabis is the versatility of its growing cycle. There are several different methods you can use to sprout your autoflowering cannabis seeds, all of which are equally effective.
Growers can easily germinate autoflowering cannabis with materials that are readily available in their own homes. One simple method for autoflowering cannabis seed germination is using plain water. To begin, fill a small glass with room-temperature water. If you use water from a tap, you may want to invest in a pH monitor to ensure that the pH of your water does not exceed 7.3.
Next, scoop your autoflowering seeds into a spoon – it is extremely important to handle them delicately–and gently slide them into the glass: the seeds should fall and float on the water’s surface.
Having followed these steps, you can proceed to relocate the cup into a proper environment. Place the cup of water with your seeds in a dark environment (the darker, the better) with an average temperature of 75 to 80 degrees. After completing this step, your work for the germination phase is done; simply leave your seeds undisturbed for two days, and check back to see if they’ve sprouted–if they haven’t, continue to leave them in the same environment until they sprout.
The “paper towel method” is another easy way to sprout autoflowering seeds with materials that you’ll already have in your home. This method involves using a wet, folded paper towel and a plastic container to sprout your autoflowering cannabis seeds.
This method is easy and produces rapid results. To begin, you’ll need a wet paper towel and a plastic container with a lid.
Begin by cleaning and drying your plastic container to ensure a proper germination environment. Next, fold a paper towel two to three times over, then saturate it with water: though you’ll want your paper towel to be soaked all the way through, it should not be dripping water.
Next, cut two holes in the top of the lid of your container; these perforations will allow excess water to escape the container during germination.
Having done so, place your autoflowering cannabis seeds on the wet paper towel, tucking them between folds to ensure that the seeds are in direct contact with the paper towel on all sides. Proceed to place the folded paper towel with your seeds inside inside of your plastic container, and fasten the lid.
Like any other germination technique for autoflowering cannabis, the paper towel method requires a proper germination environment–and darkness is the most important factor. Store your container in the darkest possible environment. With this, your work is done: simply wait for two days to check on your seeds, which will likely have germinated–if they haven’t, continue to check the container until they sprout.
You can also germinate your autoflowering cannabis using seed starter cubes, which are easily obtainable online. Do some research to find the best starter cubes, which you will place knuckle-deep into your soil. Be sure to have your hole ready before you insert your starter cube with your autoflower seeds inside.
Make sure that your cube is moist–if it’s too dry, moisten it slightly with distilled water. Then, gently pick up one of your autoflowering cannabis seeds, and insert it into the the premade hole at the top of the starter cube. Next, insert the starter cube–with the precut hole and autoflower seed facing upwards–into a hole in your soil.
Finally, place a cup overtop of where you inserted your seed starter cube in your soil. Leave the cup in place for at least seven days after you plant your starter cube; this will help retain humidity levels during the germination process. Once your seed has sprouted, you can remove the cup and move into the next phase of the growing cycle.
Though the aforementioned methods are easy and great for beginners, some growers prefer to use soil as a natural medium. This will require specialized resources such as a pH monitor, the correct soil for growing, and a humidity monitor.
To sprout your autoflowering cannabis, begin by moistening your soil and establishing a proper growing environment with an average temperature of 77 degrees. Ensure that pH levels do not exceed 7.3 . Finally, dig a hole of the appropriate depth in the top of your soil, and bury the seed inside.
The Advantages of Autoflowers: Quick, Easy, Methods to Sprout Your Autoflowering Cannabis Seeds Germination
As you can see, sprouting autoflowering seeds is easy and produces rapid results. It is also cost efficient, as many of these methods involve materials that most people already have in their homes. Growing autoflowering cannabis is much faster and easier than growing photoperiod plants; using these easy germination methods, your autoflower seeds will sprout in no time, and with minimal effort. And the easy part doesn’t stop there–every stage of the growing process for autoflowering cannabis is rapid, productive, and easy for all growers, no matter their experience.
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.
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 of the seeling
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!
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24 thoughts on “How to Germinate Cannabis Seeds”
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?
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!
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 .
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,
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.
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,
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.
Good morning Mary Jane,
Thanks for your support, and for sharing your experiences with germination!
You might also be interested in our article on The Life cycle of Cannabis: From seed to harvest.
Have a great day!
What happend if they sink I had em sink they came out fine
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..
Are you saying they sprout in the glass of water and don’t “drown”?
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
Take aluminum foil flatten it out and put on top of your dirt it detects planes and grow it just like a tomato plant
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,
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.
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
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!
With best wishes,
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
This article, about how to water cannabis plants, should answer your questions. I can’t help you with the clingfilm one though, as it depends on the climate. Good luck, and happy gardening!
With best wishes,
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.
Good afternoon Graham,
Thank you so much for sharing your experiences with germination.
Thanks again for your comment, and I hope you continue to enjoy the blog.
Have a great day!
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.
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?
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,
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