Germinating cannabis seeds can be a bit stressful. They generally aren’t that hard to get started, but many seeds cost $8-10 or more each. That’s not so bad if you just buy one – although then it’s stressful wondering if you’re going to get anything. And if you buy five the expense adds up. So germinating them and starting them off properly is really important. Unfortunately there’s a lot of misinformation and half-understood advice floating around…
Many people insist using wet paper towels is the best way to get seeds to ‘pop’ and I’ve done this myself with reasonable success. But it’s definitely not the best solution for a number of reasons:
- It’s easy to let the paper towel dry out, and that is generally fatal to a just-sprouting seed
- It’s very tempting to keep opening up the paper towel to peek at the seed’s progress, which stresses the newly emerging root by exposing it to air and light; that can be fatal
- Many paper towels will have traces of chemicals in their fibers, and those can put stress on the seed as it tries to get started
- Many paper towels also have fibers that seed roots like to work their way into, which makes it hard to transfer sprouted seeds to their next stage growing medium without damaging the roots. (Ironically, the worst kind of paper towels for this are generally the more expensive ones.)
- Transferring sprouted seeds from their paper towel birthplace to anywhere else exposes the new root to light and air and physical damage, all of which are bad news to the new wannabe plant
It is MUCH better to start your seeds off in small ‘grow plugs’ of some sort and simply move those into whatever they will eventually live in once the roots start growing through the starter plugs. If you plan to grow in some kind of hydroponics system (NTF, DWC pots, or some other variation) use Rockwool cubes, as these are fully inert and won’t introduce any possible organic substances to your water. But these do have a tendency to be slightly higher in Ph (acidity) level than is ideal, so if you’re planning on planting in soil, try peat plugs or a similar kind of medium. (If you have Rockwool starter cubes don’t get too worried, just make sure you flush them well with neutral Ph water.)
This ‘how to’ site explains why it’s a good idea to use ‘peat pellet’ grow plugs when germinating your cannabis seeds:
I use Root Riot grow cubes. I’ve tried various others and these consistently give me the best results. Just look up ‘Root Riot’ in Amazon or your preferred grow store.
Whatever kind of grow plugs you use, keep them and your seeds somewhere between 63-80°F (18-26°C), keep them moist but not soaking, and watch for the first leaves to appear. Once this happens you’ll need to give them light as well, but also make sure they don’t get too dry from having a light source close by. The clear plastic covers of seedling trays are made for exactly this task.
Once they’ve grown enough for root tips to start pushing through the grow plugs it’s time to transfer them to their larger home. If this is an NFT tray, a 4-inch Rockwool cube is perfect. Other hydroponic systems use clay pebbles, so put the plug into those. For soil, make a hollow in the medium, bury the grow plug in it, and give it a watering to welcome it to its new home.
Before you germinate anything, and before you even order any seeds, aways be aware of the local laws about growing cannabis. Some places it’s fine for personal use (up to a certain number of plants, always in single figures), some places you need a license to grow your own, some places it’s legal to own seeds but not to germinate them (yeah, weird huh?), and some places even owning seeds isn’t legal. Think carefully before growing where you can get in trouble. Discretion and careful planning are essential if you choose go ahead.