Each germination method below require certain environmental factors in order to develop quickly and remain healthy.
- Temperature: During the germination period, the temperature of the space should be between 22 and 25 degrees Celsius. You can use lights to create this warmth, but make sure the seeds are covered with an opaque lid, since exposure to light can be detrimental.
- Humidity: During the germination and sprouting period, the humidity should be between 70 and 90%. You can install a hygrometer to ensure the proper moisture level.
- If the area around the seeds is too dry, the first little root – called the taproot – will die before it has even begun to grow.
- Incandescent or fluorescent bulbs are fine for providing heat during germination.
- Avoid touching the seeds, and especially the taproot – with your hands.
Different Germination Methods
There are many different ways to germinate your cannabis seeds. Some growers choose to purchase a special seedling starter kit, which will often provide the growing medium, trays, instructions and even a germination supplement. While a complete set of equipment can be useful, particularly for new growers, this is certainly not required. Cannabis seeds can be germinated successfully using basic tools you already have around the home.
Regardless of the method, cannabis seeds will take, on average, 24 to 72 hours to develop a root. This first little extension, the taproot, is the appendage from which all future roots will grow. Though one to three days is the average length of time, you should allow your cannabis seeds up to two weeks before giving up on them. Various factors, including some you cannot control, can slow germination.
One popular way to help cannabis seeds enter the germination stage is with damp paper towels. In this simple method, the damp towel is placed on a plate or tray, and the seeds are set on top. They should be spaced out as much as possible.
Another damp paper towel (or, if you prefer, a few towels) is placed on top of the seeds. Then an opaque lid or second plate is set over the seeds. This cover is essential to keep the environment moist and dark – two vital factors for cannabis germination – but it must not place any pressure on the seeds.
You can check under the lid each day to see if the root has appeared, and ensure the seeds are suitably moist. While the seeds germinate, the paper towel must be kept damp, but not wet. Mist the towels with a spray bottle when required, but take care; if the environment is too wet, one of two things may happen:
- The germination period will take much longer. Because the root does not have to extend to seek water (since there’s so much right there), it will not grow as quickly.
- The seeds or small root will rot.
Glass of water
The first day or so of the cannabis seed’s life can be spent in a cup. Simply drop the seeds into the water. They will float until they have absorbed enough water, and then will sink to the bottom of the glass.
The seeds should be removed from the water when the taproot is 2 or 3 cm long, but don’t leave them to soak for more than about 36 hours. If the seeds still have not sprouted a root at this time, remove them from the water and use the paper towel method until the taproot appears.
This germination method is best suited to seeds that are very hard, or those that are more than a year old.
Direct to SoilAnother cannabis germination method involves planting the seeds directly into soil, as many gardeners do with their produce seeds each Spring. For this method, it is best to use a high-quality potting soil that has a good amount of nutrients and is free of any unknown contaminants, which could harm the fragile seedlings.
Ensure the soil is very lightly packed, so the small roots don’t have difficulty pushing through it. Make a small hole in the soil for the seed and wet it slightly, then place the seed in the hole and cover it gently with a bit of soil. Again, don’t pat the soil down, as this may make it difficult for the stem to push through. Make sure there is good ventilation in the room where the seeds are undergoing germination.