Soil is an easy, more natural method with which to germinate your cannabis seeds because the soil protects the fragile roots from any interference. Photo by: Gina Coleman/Weedmaps
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.
How to germinate cannabis seeds
When a seed enters an environment with enough moisture, it will increase in size and slowly break out of its shell. A seedling or germ forms from which roots will emerge, helping the baby plant absorb nutrients from the soil. Seeds naturally develop roots facing down and stems stretching upward, allowing the young cannabis plant to simultaneously feed off light and earth.
Germination itself is a crucial aspect of cannabis cultivation. The seed germination process is the foundation of every marijuana plant, and steps can be taken to boost successful popping. For example, some cultivators improve germination attempts by soaking seeds in 1% hydrogen peroxide or a compost tea for 12 hours beforehand to kill any dangerous pests.
The downside of water germination is that once they’ve popped, you’ll need to maneuver them into their growing medium manually. This is a delicate process, as germinating seeds are extra fragile, and any harm risks the development of your plants. Make sure to place the seed roots down in the soil when you transfer to a pot.
Cut Rapid Rooters in half to make it easier to insert germinated seeds
Try to place the seed head close to the top so they don’t have far to go. I’ve found that some seedlings don’t make it to the top if you put them too far down.
One downside to this method is sometimes a seed shell will get stuck on the seedling. Here’s how to deal with that.
4.) Cover with 1 Sheet of Paper Towel
Note: Move grow light down early if seedlings start getting tall with long stems. Tall, stretchy seedlings are telling you they want more light.
Gently close around the seedling
At this point, the seedlings are ready to be put under a gentle light. A sunny window works well, though your regular vegetative grow light should be fine as long as you keep it twice the normal distance away. Avoid touching the seedlings if possible. This is when they’re most vulnerable.
Seedling heat mat to keep seedlings warm (or any surface that’s about 70-85°F or 20-30°C)