I’m an outdoor grower. Occasionally I grow a plant or two outdoors in big pots, but mostly my plants go into my garden, so past the germination stage my reporting is not applicable to people who are growing their crop indoors in pots, in a greenhouse or hydroponically. Backing up from the May 24 weekend my growing process starts Mid-April. Cannabis seeds generally germinate in 5-6 days, seedlings are then ready to go under lights for 4-5 weeks and must be carefully transferred to small pots filled with a light, loose starter soil, preferably without chemicals.
It’s possible to grow cannabis plants without lights, but seedlings grown under lights for a few weeks prior to outdoor planting have a larger root ball, are stronger and grow bigger in my experience. The lights themselves can be readily purchased on the web. I bought a couple of small ones that hang over a counter top and sink in my furnace room. This part of the process is touchy. Failure can come without warning and many things can go wrong. I tend to over-love my plants, overwater and overwatch (that is standing and looking at them for minutes at a time).
I’ve learned many of the following tips by experimentation, research and expert consultation however stuff happens for which there is no explanation.
Pots: Eventually the seedlings must be transferred gently from pots to garden. The best kinds of pots to use are the flexible plastic ones I’ve saved from plants purchased at a nursery. Roots tend to cling to hard-sided plastic or clay pots, tearing off and making the root that’s been developed under lights less viable.
Watering: Unfortunately there is no tried and true method for watering cannabis seedlings. I’ve never found a specific schedule that works all the time. People who over-love their plants also tend to over-water them. The growing medium must stay light and loose. Poor drainage will cause brown leaf-tips and if continued the plants will die. If too dry ditto. I have an RO water system in my house and I’ve always taken pride in growing organic cannabis. This year I discovered that cannabis plants require some of the minerals found in tap water and that RO water should only be used to flush roots before harvest. One of my friendly consultants then advised that I should fill large open containers with tap water and allow the chlorine to evaporate before watering.
Fertilizer: Seedlings require little or no added nutrients until they are 2-3 weeks old. I use only organic, fish-based fertilizer. Less is more. The wonderful expensive organic liquid fertilizer I buy from the local head shop has good instructions. I can’t say that I’ve succeeded in discovering the ultimate way to fertilize a cannabis seedling. Because I tend to over-love, I also tend to over-fertilize.
Lights: Brand new seedlings must be placed very close to the grow light, in the beginning, about an inch below. One of my consultants told me that I should hold my hand between the lights and the seedling and be able to feel heat. As the seedlings get larger they need to be moved further away from the lights. Another consultant told me to occasionally pass my hand slowly between the lights and the seedlings, transferring my positive feelings. I’m not sure if this is effective but it doesn’t hurt to try. The days under lights can be stressful for the first-time grower but less so each year, particularly if said grower keeps good records and learns from experience.
Environment: The growing room must be kept warm and have good air circulation.
Cannibis is a marvellous plant. I can clearly see the day when people who love to garden start to grow it as part of a garden versus for medicinal or fun purposes. The really good part of growing MJ comes next when the seedling goes into the ground and becomes a plant. The stress of germination and seedling management is over. The only stress now comes from worrying about someone stealing my plants, or bugs or animals eating them.