The seeds should start sprouting in about two days, though older seeds can take up to a week to sprout. You can remove them from the water and place them in the soil at any point once they’ve sprouted. Once the roots are about five millimeters long, they need to be planted.
While many plants can be germinated in the ground, cannabis seeds are fragile enough that you should germinate them before planting.
When the seedling stems reach two to four inches in height, it’s time to transplant your cannabis into larger pots with more room for roots to spread down and out. After you’ve done this, you’ve successfully germinated your cannabis seeds into proper, young plants.
How to germinate seeds in water
Gently water the soil with a spray bottle and situate your pots under a fluorescent lamp. Keep seeds away from the windowsill, as the temperature is too volatile for germination. In general, you’ll want to keep the temperature in the range of 70 to 80 degrees Fahrenheit.
First, make sure you use the correct type of soil, either gently fertilized potting soil or a seed starter with a pH level of approximately six (6). The soil contains the right acidity and enough nutrients to strengthen your young cannabis plants for the first two weeks. Be careful not to add more nutrients, or you risk overfeeding and killing your seeds.
The paper towel method is also a common way cultivators pop their seeds. Some even use this method with cotton pads instead of paper towels, but the necessary steps are the same.
Lay one paper towel on top of a countertop, place a few seeds, and cover them with a second paper towel. Photo by: Gina Coleman/Weedmaps
So there you have it: whichever method you chose, germination should now be underway. Remember that even the best seed banks work with organic, natural materials, so 100% germination rates can never be guaranteed. If you get your technique right, though, most or all of your seeds should germinate according to plan. Once your seeds have become seedlings, the next steps of your grow await. There’s a lot of choices to make from here to harvest time: indoor or outdoor, which spot to pick, what nutrients to use, and so on. Keep an eye on our expanding grow blog collection if you want to learn more!
Cannabis seeds and sprouted seedlings require constant temperatures of around 20-25 degrees Celsius
For this method, simply prepare your medium by moisturizing it, again, without soaking the soil completely. Then take your flower pots and use your finger to make a small hole about 10-15mm deep in the top layer to put the seed in. Cover the seed up loosely and top it off with a little water. Be careful not to give too much at once though! A stream of water can cause the seed to travel further down the pot where it’s too moist – and too deep to travel back up again.
How To Germinate Cannabis Seeds in Plugs
Plugs are a practical way to germinate cannabis seeds
This is the part where most growers (especially the hasty ones) sometimes lose a seed. Remember that you are handling a baby plant here. The vulnerable root is easily damaged during the transplant. If you don’t trust your steady hands, it might be better to choose another germinating method.
After the root has sprouted and has gained a few millimetres in length, it’s time to transplant the seedling into its soil and put it under a light-source. As a rule, a small 1cm deep hole made with your fingertip should do. Gently pick up the seeds one by one, taking care not to touch the root. Use a clean pair of tweezers and don’t squeeze. Make sure that the roots don’t cling to the paper or cotton wool. Lovingly cover the seed with a little (loose) soil and add a few drops of water. Now, all you can do is wait whole the story continues below the surface. As soon as the seedling pops her head above the ground and green leaves emerge, she’ll needf light to continue growing.
Most plugs are dry blocks of (usually) coco fibre. Peat plugs are an interesting alternative, as these contain some initial nutrients to help the seedling along. After fully absorbing about 500ml of moisture, or 250ml of a root booster and another 250ml water, they slowly turn into a moist, soil-like plug. Grow plugs usually have a premade hole in which to place the seed. After sticking the seed in the top of the plug, cover it lightly with a little leftover plug fibre. It takes a few days at maximum before you see the first heads pop. As soon as the roots grow out of the bottom or the side of the plug, you can stick the entire plug, complete with its seedling, into your intended medium. These plugs make germination and the initial transplant a piece of cake.