Posted on

how to germinate cannabis seeds indoors

Cannabis seedlings usually emerge from the growing medium 24 to 72 hours after the germinated seeds are planted.

Place the cannabis seed, root first, into the hole and cover with a small amount of growing medium – just enough to block light, not enough to obstruct the seedling when it emerges.

Seedlings intended for outdoors should be acclimatised to direct sunlight by placing them on a windowsill inside the house and increasing their exposure to direct sunlight by an hour or two per day.

Step 3. Potting – How to germinate cannabis seeds

Make a hole in the growing medium that is about twice as deep as the seed is long, so that each germinated cannabis seed sits 2-5mm below the surface.

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.

Seeds should be placed on top of the tissue, allowing each seed as much space as possible.

Place the plates somewhere warm (21ºC) and away from direct light.

Germinating cannabis seeds doesn’t always go as planned. Some seeds will be duds. Others will be slow and take longer to sprout. But some will pop quickly and grow rapidly.

Males will have round balls—these will develop into pollen sacs, which will release pollen into the air when mature.

Most experienced or commercial growers will not use feminized seeds because they only contain one set of genes, and these should never be used for breeding purposes. However, a lot of beginning growers start with feminized seeds because they eliminate the worry of having to deal with male plants.

Step 3

A lot of classic weed strains that have been around for a while come in feminized form. Some popular fem seeds are:

Cannabis seeds require three things to germinate: water, heat, and air. There are many methods to germinate seeds, but for the most common and simplest method, you will need:

Autoflowering seeds are also popular with beginning growers. They are easy to grow because you don’t have to worry about light cycles and how much light a plant receives.

Check out Johanna’s full video series on how to grow weed on Leafly’s YouTube .

• The ideal temperature is between 22° and 25°C (71–77°F)
• Your growing environment should be damp/moist, but never wet
• Relative humidity range should be between 70% and 90%
• Seeds favour fluorescent lighting (Cool White code 33)
• Minimise the amount of seed handling you do
• In hydroponic/rockwool plugs, the ideal PH value is 5.8–6.2



Small, fragile, and in desperate need of a helping hand, there are several ways you can germinate your cannabis seeds. All methods have varying degrees of success, with both advantages and disadvantages. It is important to note that even with advanced growing expertise and top-of-the-line equipment, you may still end up with a few failed seeds. This is a natural part of dealing with a living organism. At Royal Queen seeds, we only sell feminized cannabis seeds, so there is no need to worry about removing male plants.

Two or three weeks after germination, your young seedlings should be ready for their new home. At this point you have two options; transplanting them into soil pots, or taking on the challenge of hydroponics. You’ll know when the seedlings are ready to be moved because the root system should start to poke out of the bottom of the wool blocks. As long as the roots haven’t begun to engulf the bottom half of the wool block, they will seek out water and nutrients in their new surroundings and continue to grow downwards.

Timescales can vary, as it all depends on how ideal your germination environment is (see the golden rules above). Even the worst grower could make a seed germinate, but it may take a few weeks and, of course, increases the risk of a weaker plant.