Read this article to learn about the best conditions for your cannabis seedlings. Learn about optimum temperatures, light exposure, air conditions, and the equipment you’ll need to get the best possible results.
Once the young plants produce their second or third pair of serrated leaves, or if they grow taller than about 7 cm with only the first pair, the cover of the propagator should be removed. A small oscillating fan on the lowest setting is a good way to give indoor plants the air movement they need, while outdoor plants can start to receive the natural outdoor air movement when they have reached this size.
Propagators are simple to obtain and provide an ideal start for young cannabis plants. A propagator is a plastic tray with a transparent top which holds in humidity and warm air while allowing seedlings to receive light. This an easy way to maintain a good environment for very young seedlings . However, since the cover prevents normal air movement (which is very important as it encourages young plants to grow strong stems), cannabis seedlings should not be kept in a covered propagator for too long.
The simplest form of propagator would be a waterproof box with clear plastic sheeting over the top. The advantage of shop-bought propagators is that they often have built-in heating and/or vents in the cover to allow temperature and humidity regulation. They also usually allow more light to reach the seedlings.
After seeds are sown in the growing medium, they can be placed in a propagator for the first couple of weeks.
The best way to germinate cannabis seeds requires only two saucers or plates and some moist tissue. Here is a step by step guide.
Place the plates somewhere warm (21ºC) and away from direct light.
Step 1. The setup – How to germinate cannabis seeds
Lastly, cover everything with the second plate, upside down, to form a ‘clam-shell’ shape – this will create the dark, moist environment necessary for germination.
Cannabis seedlings usually emerge from the growing medium 24 to 72 hours after the germinated seeds are planted.
When the first few millimetres of root have emerged from a germinated seed, each one should then be carefully transferred to a small container of growing medium (soil, coco-fibre or rockwool).
You will need to invest in a few pieces of unique equipment, but by using stone wool blocks, you can create a perfect utopia for germinating cannabis seeds. Soak the stone wool blocks in the same way you would a soil medium. The wool will retain the moisture and prevent the need to water during the early stages of germination. After the wool blocks are soaked, stick them in a plastic tray that also has a lid. Large cake tubs are ideal.
The dome of the plastic container will create your seeds’ own mini tropical climate. If you then place all the components in a temperature-controlled cupboard, you will have created a self-perpetuating supply of moisture—no need to touch the seeds again until they are ready to be transferred to your final growing medium as a young seedling. Using the stone wool block method, your seeds should germinate in one to two days.
Start by filling pots with a premium-quality soil that has been soaked in water. Many growers also choose to lace the water with a root stimulator. Make a hole roughly 10–15mm deep. This will be your seed’s new home. Remove the seeds from their packet and place them into the pre-dug holes. Loosely cover the seeds, but be careful not to compress the soil above the seed too much. The root will struggle to penetrate solid soil, slowing plant growth. Lightly spray the top of where you placed the seed so that your growing medium stays moist.
PLANTING DIRECTLY INTO SOIL
Place one sheet of damp kitchen towel on a flat surface. Space your seeds a few centimetres apart before placing the second piece of kitchen towel over the top. You need to ensure both pieces are damp, not wet. Once again, when the white root tips reach 2–3mm, move the seeds (carefully) to soil pots. Use the same guidance found above for planting techniques.
Often overlooked, it is all too easy to assume that the vegetative and flowering stages of cannabis growth are the most critical parts of the plant’s life cycle. However, with the chance of failure high unless you know what you’re doing, poor planning when it comes to germination can make or break your next grow. Giving your cannabis seeds the best possible start on their journey to bulging buds is a surefire way to encourage a healthy and robust plant.
Three fundamental principles will trigger that first small taproot to appear: warmth, moisture, and darkness. With the promise of moisture, a single root will take shape before slowly developing into the cannabis plant we know and love. In the right conditions, seeds will begin to develop within 12–36 hours of moisture being introduced to them.
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.