In this guide on how to germinate cannabis seeds, we are going to cover everything you need to know about “popping beans.” If you follow the steps in this guide and have quality cannabis seeds, you should see your seeds pop every time!
We will cover a few different methods of germinating cannabis seeds in this post so that you can choose the method that works best for you and the medium you are growing in. But before we discuss those things, let’s talk about why it is so important to know how to germinate cannabis seeds properly.
Why Proper Germination Matters
Let’s say you want to grow four plants. You take four seeds of your favorite strain and begin germinating them. Now, if you haven’t used a good germination technique, these seeds may not pop. That is not only a waste of money but also a waste of time.
If only one or two out of the four seeds germinate, you’ll need to germinate additional ones to compensate for the loss. This means the newly sprouted seeds will be behind the others by about a week. This can really mess with timing of the grow.
Also, what happens if the seed you were trying to germinate cost a lot of money, or they are some heirloom genetics that you can’t get anymore?
Proper germination is important; it is always a shame to see good seeds go to waste. So make sure, before you germinate any seeds, you follow this guide thoroughly. Choose a method that works well for you and stick with it.
How a Germinating Cannabis Seed Works
A cannabis seed is pretty much a tiny cannabis plant, compacted into a hard shell with a little bit of food stored up.
Introducing water to the seed softens the shell, allowing a small amount of moisture to penetrate into the seed. This triggers the seed into action, and the root cap starts to push its way out of the seed casing. This turns into the taproot.
The taproot will grow deeper into the grow medium and spread out to collect nutrients and water. The cotyledons (little round leaves) will then push their way above ground and eventually push the seed casing off so the leaves can catch light and start making food via photosynthesis.
It’s a simple process that only takes a few days to complete, as long as you have used a good technique, of course.
How to Germinate Cannabis Seeds: A Step-by-Step Guide
First off, before you do anything, it is a good idea to let your cannabis seeds soak in room temperature water for a few hours. Overnight is great, but some people like to wait a full 24 hours. This is just to soften the shell a little and make it easier for the tap root to push itself out.
However, this technique was used “back in the day” to check if cannabis seeds are viable or not. Dozens of seeds would be added to water. Those that sank were no good, and those that floated were viable. We don’t have to do this so much nowadays because seeds are very reliable if you got them from a good cannabis seed bank. As a result growers would only do this nowadays to soften the shell of the seeds a little.
So, if you are germinating cannabis seeds now, go and place your seeds in some water. While they soak, you can decide which method you are going to use to germinate your cannabis seeds. There are two main methods to choose from: the paper towel method or planting it into the grow medium.
The Paper Towel Method to Germinate Cannabis Seeds
The paper towel method is where cannabis seeds are placed between a few layers of damp paper towels. The paper towels and seeds are then covered with Saran wrap/cling film to lock in the moisture. Then, they will be stored somewhere warm for 24-48 hours until the taproot shows. At that point, they are planted into the medium.
It’s a very simple process, and it works great for germinating cannabis seeds. But if the towel dries out, the seeds will die. You may also damage the taproot when planting it into the soil. So this method is not without its issues.
The paper towel method was used “back in the day” because seeds were a lot less reliable. You would know how many would pop, and how many wouldn’t. So using the paper towel method allowed growers to see which seeds popped out a taproot so they could plant those. Instead of preparing lots of pots with grow medium for seeds that would never pop. It isn’t needed as much nowadays because seeds are so reliable. Instead, many growers prefer to plant straight into the medium.
Planting the Seeds into the Medium
After soaking your seeds for a while, you can just go ahead and plant them into the grow medium. Begin by watering whatever grow medium you’re going to use. Make sure it is good and wet and ready for a seed to be planted.
Then, make a small hole about 1cm (⅓ Inch) deep, and gently place the seed into the hole. Once placed, simply cover the seed lightly with a small bit of medium. Do not pat it down, just cover the seed and leave it as it is.
Finally, you need to cover the seed with some kind of humidity dome to hold in the moisture in the air. This will massively increase the chances of successful germination. Try using a plastic cup turned upside down; I find those work great! Some mediums, however, may be packed full of nutrients. This can shock the seeds and kill them before they even get started. So choosing the right method of germinating cannabis seeds will also depend on what grow medium you’re using.
Selecting the Right Medium for Germination
There are many different mediums you can use for germinating cannabis seeds. Some are much better than others. For example, some super soil is packed full of nutrients. This can be too much for a new seedling, and the taproot can get shocked. This will kill the seedling.
On the other hand, you can use rockwool cubes, which are completely void of nutrients. But, they can dry out quickly. If the rock wool dries out, the taproot will dry out too. This, again, will kill the seedlings.
Here are just a few examples of different mediums you can use for germinating cannabis seeds. The one you choose will differ depending on your grow setup and which medium you use for your grow.
How to Germinate Cannabis Seeds in Soil
Germinating cannabis seeds in soil is relatively easy if the soil is a light mix! Cannabis seedlings can be shocked easily if a grow medium they are placed into is too “hot” (has a lot of nutrients in it).
For cannabis seedlings, it is best to start the plants in some light soil like a potting mix. Potting mixes usually have a lot fewer nutrients in them than standard soils. This can reduce the risk of shock to the roots.
You can also use some coco coir or jiffy pellets to get the plants started, and then plant into soil when the roots are established. Of course, you can try using the paper towel method to let the taproot grow a little, and then plant it. But you still may shock the root if the soil is too strong.
My recommendation would be to use potting mix or coco coir for the first week or two, then transplant into the stronger super soil if that’s what you’re using.
How to Germinate Cannabis Seeds in Coco
Coco is a great grow medium that holds the perfect amount of moisture. It is perfect for germinating cannabis seeds. After soaking the seeds overnight, all you have to do is plant them into the coco.
Prepare the coco beforehand by making sure it is watered and has a small amount of nutrients in it. Pretty much you should water the coco before the seed is in it, like there was already a plant in it. Prepare the coco, create a shallow hole in the center approximately 1cm (⅓ inch) deep. Then place the seed into it and lightly cover it with coco.
Now, just place a plastic cup or humidity dome over the coco and seeding to lock in moisture and wait a few days. You should see the seedling shoot out of the coco in 3-4 days.
Using Rockwool Cubes to Germinate Cannabis Seeds
If you are growing in full hydro setups, you may be germinating your seed in rockwool cubes. For the best results here, you should begin by using the paper towel method to get a little of the taproot going first.
Next, prepare the rock wool cubes by watering them well with a nutrient solution. Much like coco, water the rock wool cubes like there was already a plant growing in it. There should already be a small hole in the middle of the cube, but if there isn’t one, make a small 1cm deep hole in the cube. Then plant the seed in it and cover the seed with some of the rock wool.
Finally, place the rock wool cubes in a propagator to lock in moisture. Keep them damp, check on them daily, and within a few days, you should see your seedling shoot out of the top.
Preparing Your Environment
At this point, your seeds should be in the grow medium with some kind of humidity dome over the top to lock moisture in. Now, you have to store them in the right conditions to improve your chances of germination. It is best to think of it like nature. Seeds will germinate in the springtime. It will be cool, but not cold, and the air will be humid. You should try to simulate this for your seedlings if possible. The humidity domes will lock in the moisture, so make sure you have one of those.
When it comes to temperatures, room temps are usually fine. Anything above 12°C will work. You just don’t want it being so cold it’s close to freezing or too warm that it kills the seed.It is not recommended to use heated propagators; they can get too hot and damage the seeds. Room temps are fine. Just put the seedlings in their grow medium and store them somewhere dark and warm. Then you just have to wait, which is harder than you think.
Try not to disturb them for at least 3 days; after this long, they may need to be watered.
How to Water Cannabis Seedlings During Germination
So, right now, you should have some seeds that are sitting in the grow medium, in a warm dark place, waiting to pop. This can take a few days, and in some cases, the grow medium might start to dry out. If it dries out, the root will die, and so will the plant. It is very important to keep the medium wet.
But, and this is important, if you water incorrectly, you could damage the seed!! Watering the medium too quickly may cause the seed to float, dislodging it from the grow medium and potentially causing significant root shock or breakage. Therefore, it is important to water with slowly to avoid damaging the tap root.
It may be a good idea to just spray the top of the grow medium with a mister spray, then replace the humidity dome. If you don’t have a spray bottle, just pour some water slowly around the edges of the pot or rock wool cube. Never in the center where the seed is. You don’t want to dislodge the root.
You shouldn’t need to water, but if you do, follow these guidelines. If you need any further help or advice on this, just come and ask for help in the forum. We are always happy to help.
When to Give Seedlings Light after Germination
After a few days, you should see a shoot pop out of the grow medium. Do not remove the humidity dome yet. Sometimes the seed casing can get stuck on the cotyledons. Having high humidity in the air will soften the seed casing, making it easier for the cotyledons to break it off.
When the seed casing has fallen off, and the cotyledons open up so you can see the green on them, get a light over them! The light is not really necessary until the greenery shows. But as soon as the greenery does show, the plant will need light to make food using photosynthesis. If you do not give the plant enough light at this stage, it will stretch reaching for the light. It is important to give the plant light when it shows greenery.
Once the humidity dome is off the plants too, add a light breeze using an oscillating fan. This will help keep the plants short and strong, and it will reduce stretch too.
Common Mistakes to Avoid When You Germinate Cannabis Seeds
Here are a few common mistakes new growers make when they start germinating cannabis seeds. They are just minor things, and they are easily fixable. But they are best prevented.
Do not Disturb!!
It is so easy to do. But really, if you have followed the steps above, the seed will germinate; you just have to be patient. Don’t take off the humidity dome, don’t try moving the grow medium out of the way to see if you can see the seed or taproot, just leave it alone.
You shouldn’t start to get concerned until after 5-7 days. If you haven’t seen any seedling in that time, there may be a problem. We explain what you should do in these circumstances later in the article.
Do not Plant the Seed too Deep
New growers will often plant their seed a bit too deep. This makes it more difficult for the taproot to grow, find nutrients and give the plant what it needs to reach the surface. All you need to do is plant that seed no more than 1 cm deep. Any deeper and there may be issues.
Once the seed has popped and the shoot is above ground, you can add more soil if you wish to add more depth. But give the young seedling an easy time, don’t make it dig too far to get to the light.
Using Soil that is Too Strong
Excessive nutrients in grow mediums can easily shock seeds. Mainly, super soils. If you are growing in soil, and you keep losing seeds during the germination stage, it may be down to the strong soil.
Consider starting the seeds off in coco coir or jiffy pellet, or maybe even potting mix. Then transplant the seedling into your main soil when it is more established.
Add the Fan and Light
Once the seedling is above ground, it is looking for light! If it doesn’t get the light, it will stretch! Depending on the light you have and how much light it puts out will dictate how far away from the plants your light should be. Around 18 inches is the average distance. If it’s too close, it’ll shock the seedlings; if it’s too far, the seedlings will stretch trying to reach it.
The distance will depend on which light you’re using. So check the manufacturer’s guidelines or ask for help in the forum.
But what also will encourage stretch is no wind! As soon as the seeds pop out of the medium, add the light, but also add a fan. Nothing too strong, just a light breeze oscillating around the grow room. This encourages the plant to build a strong stem as it grows. So it more focuses on stems getting thick and sturdy, rather than tall and thin.
What to Do if a Seed Doesn’t Germinate
If you have followed all of these instructions, and after 7 days you still haven’t seen a shoot, there is an issue with your seed. But this happens sometimes too. Try to move some of the grow medium away from the top of the seed to see if you can see it. If you can, see if you can spot a taproot.
It is important to try not to damage the root if it is there, but essentially, you’re trying to see if the seed germinated at all or not. If it has germinated and stopped, then I’m afraid the seed is dead, and you need to start again. But if the taproot didn’t come out at all, there may just be trouble with the seed casing.
Try scarifying the seed by lightly scratching it with some sandpaper or a nail file. Then, soak the seed in some water again for 24 hours. Then use the paper towel method to try and get the seed to germinate. With a little persistence, you may get it going. But be prepared to start some new seeds if you have to.
Conclusion:
I think that is just about everything you need to know about germinating cannabis seeds. It really is a simple process, and the less you have to do during it, the better off the seed will be. Prepare the medium while the seeds are soaking. Then plant the seed 1cm (⅓ inch) deep and cover with a plastic cup or humidity dome. Now, you just wait. Be patient!
Why not take this time to write the first post on your grow diary? Let us know what method you used to germinate, what medium you’re using, and what strain you’re growing. It is a great way for others to learn from you and a great way to document your progress too. I hope this guide has helped, but of course, if you need any help, just ask in the cannabis growing forum or comment on this post below. Have fun and good luck with your grow!
The post How to Germinate Cannabis Seeds for a 100% Success Rate appeared first on Percys Grow Room.
