However, the Rockwool method also has some drawbacks. The material does not break down since it is not a natural substance. As a result, the cubes are not an eco-friendly option. Rockwool has poor germination rates, and it comes with a high pH level. The material also can affect your health. The Environmental Protection Agency found that the fibers in Rockwool can irritate the skin, eyes, nose, and throat. You may experience a sore throat or coughing.
One benefit of the paper towel method is that you can leave sprouted seeds in the towel for a while longer. It allows other seeds to catch up, and you can plant them all at once. Otherwise, you can plant the germinated ones as soon as the taproot appears.
Another common method is to put the cannabis seeds in some soil. In nature, they sprout their taproots in soil, so growers may choose to germinate them directly in the medium. Prepare fresh soil by putting them in a pot or a container. You may want to use a small pot and transfer the seed to a larger one later. Next, add enough water to make it damp but not soaked.
At first, the seeds will float, but they will sink to the bottom after a few hours. Carefully push them down if they are still floating. You can leave the cup in a kitchen cabinet or dark area. Keep the glass there overnight or for 18 to 36 hours. Try not to leave them soaking for more than 36 hours. If there are any seeds that have not finished germinating, leave them in a moist place until they sprout.
Next, place the cubes into the bowl and let them soak for one hour. After an hour, take the Rockwool out. They can maintain the correct water-to-air ratio, so it is important not to squeeze the cubes. Like regular starter cubes, Rockwool usually comes with holes already in them. If not, make one that is a quarter-inch deep. Carefully insert a seed and push them to the bottom. Cover the top of the hole and wait. The seedlings finish germination in an average of three days.
Other than drying out over time, one disadvantage of the paper towel method is that there is a chance of hurting the taproot. Be careful when checking on the seeds, and do not move them too much.
One benefit of the soil method is that transferring the seedling to a bigger pot is simple. The cannabis is less likely to become stressed and can adapt to the new environment quickly. A disadvantage would be needing to buy clean soil rather than using some from outside. Pathogens in the dirt can damage the young seedling. Soil density can be an issue with air flow, and growers need to be careful about the seed placement.
If you don’t like the idea of pre-soaking your soil, you can use a spray to moisten the holes before you plant each seed. With enough moisture surrounding your seeds, you can still encourage a root to develop.
There is, of course, a far simpler way to germinate seeds. Ideal for beginners, the feminized starter kit by Royal Queen Seeds has everything you need to kick-start your next cannabis project.
To avoid disappointment, seeds that have a darker colouration stand a better chance of germinating, while pale green or white seeds are likely to fail. Even if dark seeds look slightly damaged, they should be planted anyway. There is a good chance they will still germinate, even if the outer shell is somewhat crushed.
WET KITCHEN TOWEL METHOD
Probably one of the most common methods of germination. The kitchen towel method comes in several iterations. Some growers use cotton wool pads or absorbent pieces of paper. For this guide, we will be using kitchen towel as it is readily available and holds moisture relatively well.
Planting directly into your growing medium prevents having to move seeds when they are at their most fragile. That first root tip is covered with microscopic filaments that are easily damaged. Given that both a cup full of water and moist paper towels are more prone to temperature fluctuations from their environment, planting in soil is a much safer option.
Your growing pots will need to be placed in a damp climate that is within the temperature range listed under our golden rules. After 4–10 days, you should see a young seedling sprout, while the roots will have begun to develop underneath the soil. The entire plant and its soil can now be transferred to a larger pot, where normal growing routines should start.
After 3–5 days, the seeds will start to open, and you should see tiny white tips appear. Once these roots reach 2–3mm in length, use extreme care to transfer them from the water to pre-prepared soil pots.