While many plants can be germinated in the ground, cannabis seeds are fragile enough that you should germinate them before planting.
The seeds should start sprouting in about two days, though older seeds can take up to a week to sprout. You can remove them from the water and place them in the soil at any point once they’ve sprouted. Once the roots are about five millimeters long, they need to be planted.
Use a spray bottle to moisten the paper towels and then store the cushioned seeds between two plates, under a face-down bowl, or gently place them in a plastic bag. Maintain a temperature of about 72 degrees Fahrenheit, keeping the paper towel wrapped seeds in the dark and away from a windowsill. In two to five days, the seeds will pop inside the paper towel sandwich and emit tiny roots, ready to plant when they reach about five millimeters in length.
How do you germinate seeds indoors?
Place the soil in a small pot and use your finger or a pencil to push a small hole in the dirt, a bit more than half an inch deep. Insert the seed into the hole and bury it with soil. From this point on, don’t touch your seed. The young plant is fragile and knows how to position itself in the soil bed.
To employ water germination, fill a glass with tap water and let it sit until it reaches room temperature or around 65 degrees Fahrenheit. Add two to three plant seeds per cup and allow them to sit, watching for any changes. Change the water to fresh tap water every two days, making sure it stays at room temperature.
Soil is an easy, more natural method with which to germinate your cannabis seeds because the soil protects the fragile roots from any interference. Photo by: Gina Coleman/Weedmaps
You can also germinate your seeds by placing them in water. It’s slightly faster than the soil method, but you need to adjust your environmental factors accordingly. Remember, successfully germinating seeds requires a perfect balance of ideal growing conditions. When germinating in water, seeds need only 24-48 hours to pop their stems, though cultivators can keep them soaking for up to a week as needed. Water germination is faster because the seed gets all the moisture it needs immediately, and the shell softens and cracks more easily after soaking.
Things to avoid
Heating mats should be avoided unless you need it in the wintertime. A dysfunctional heating mat, or a mistake in the temperature control, can easily boil the seeds or dry up the substrate and shrivel the freshly emerging seedling. Your pots/rockwool cubes should be placed in a space with ambient room temperature (ie. 24-26°C/75-78°F). In the winter use a small electric or gas heater to warm up your grow space. You can also switch on the HPS lamp and put the pots at a close distance underneath.
A longgrow super cloche has a rugged steel frame covered with corrugated PVC. It withstands extreme weather and is therefore a good choice for protecting seedlings if you are growing in an area with stormy weather during springtime. The ventilation is regulated by circular panels at the rear ends.
What happens if one uses pre-germination methods?
Humidity domes are only required for rooting cuttings.
Start with a mild EC such 0.7-0.8 and slowly increase the EC of your nutrient solution after one week of growth. The best EC depends on the quality of your water and it's basic EC level. If the water has a high EC then you should filter it with a household reverse-osmosis filter and mix this 50-50 with tap water.
Many growers make the mistake of thinking that they need a high ambient humidity for germination or seedlings. This is an unfortunate myth of cannabis cultivation. The high humidity and lack of fresh ventilation quickly causes fungus in the soil or growing medium and the seeds can rot!
High grade (30 gsm) polypropylene fleece covers these easy tunnels, creating warmth and insulation whilst allowing water and sunlight to filter through – a constant atmosphere is maintained for faster, even growth and protection against frost, strong sunlight and pests.