Immerse the rockwool cubes in lukewarm water with a pH of 5.6-5.8 until the rockwool is evenly wet. Overnight soaking is not required for starter cubes. Let the water drip off. squeeze lightly to assist. Place the seed in a horizontal position into the hole (this is the easiest method). The taproot can grow downwards assisted by gravity. Alternatively, you can also place the seed into the hole vertically with the rounded end facing up (cannabis seeds sprout by opening the shell at the pointy end where the taproot grows out). Cover the hole with a small piece of rockwool. Choose a fluffy piece of rockwool. you don't want to tightly plug the hole because the seedling has to grow out with ease. Water the rockwool cubes with a weak nutrient solution of 10-15% of the recommended dosage (or EC 0,6) and pH 5.6-5.8. You can also germinate using pure water. Put the rockwool cubes at a warm location. Temperatures at 25°C/75°F or higher accelerate germination. Take care that the rockwool cubes do not dry out or stand in the cold (i.e. at or under 21°C/70°F). They should also not sit in water. Usually the cubes require to be moistened with pH adjusted water every 1-2 days. Use chlorine free water such as mineral water. Within 3-5 days the seedlings should appear out of the cubes.
Hot tip: to prevent the cubes from sitting in water put some perlite at the bottom of the tray for drainage.
You can switch on your lamps during germination to provide warmth or when the first seedlings appear. Since they might also grow out of the cubes during the night it's best to have lighting switched on 24 hrs.
Take 8-10 cm/3-4” (diameter) pots or a seedling tray and fill with quality potting soil. Press the soil slightly down and make a 1,5 cm/0,6” deep hole with a pencil or finger. Place the seed in a horizontal position in the hole (this is the easiest method). Fill the hole and gently tap down the soil. Use chlorine free water (preferably good mineral water without gas) with a pH of 6-6.5 to water the pots. The soil should be uniformly moist and properly watered, but not soggy or waterlogged. The pots or tray should also not stand in a tray filled with water. Use a spoon or small beaker to dosage properly if you are unsure and want to avoid accidentally overwatering the soil. Put the pots or tray at a warm location and ideally under lighting. Temperatures at 25°C/75°F or higher accelerate germination. Take care that the soil does not dry out and that the pots don’t stand in the cold (ie. at or under 21°C/70°F). Misting the soil surface with water spray is not effective. You should water the pots properly if the soil surface dries up. Within 3-7 days the seedlings should appear out of the soil. You can switch on your lamps during germination to provide warmth or when the first seedlings appear. Since they might also grow out of the soil during the night it's best to have lighting switched on 24 hrs.
What happens if one uses pre-germination methods?
Provide sufficient light. Seedlings require sufficient light (this applies to the strength and length of daylight or artificial light) and fresh air to grow. Switch on your lamp(s) as soon as the first seedlings appear at the latest. Seedlings should be moved directly under a HPS lamp if you have one. The more light your provide the better your plants can grow. Not all Mandala strains are suited for low light such as CFL lamps and fluorescents. Make sure you choose the right strain for your lights.
A simple low-cost cloche is very handy if you need to transport the pots from inside to outside daily.
Outdoors we never know what dear mother nature has in store for us; in the same way that your seeds might enjoy a week of good weather and sun, there can also be thunderstorms and low temperatures on the very day they sprout. Not to mention the large variety of birds, snails and other fauna that delight in eating those tender and tasty marijuana seedlings. Bear in mind that during their first moments of life, your plants are defenceless against many dangers that threaten them; therefore, it is your job to take care of your little ones and keep them safe. How? It’s actually quite simple, you can buy mini-greenhouses for germinating or you can use a Tupperware and make holes in it for adequate ventilation, although we recommend the first option.
– Another advantage is the specific temperature: water has a low specific temperature. This means that if we place a glassful of water in a room at 25°, it will be very hard for the water to reach that temperature. Therefore, if we place the cannabis seeds in a very watery medium (a glass or between paper towels) the temperature will be lower, while in a Jiffy, as it is more exposed to the air, the temperature will be higher and the process, faster.
Step 2: choose quality materials.
Today you can find high quality products on the market, specifically designed for germination and which, in addition, are not expensive. What do you need?
For indoors: The same but under a grow light, fluorescent or LED. If you have the option of germinating your cannabis seeds inside your home, ideally the light intensity will be high; the less intense the light, the more the seedlings will stretch in search of light and become spindly. If you use a 400 W light ideally it should be 40-45 cm away.
– It has all the elements necessary to nourish your seed/seedling during the first week; the ideal amount of nitrogen, phosphorus, potassium, calcium and magnesium. Phosphorus and calcium are particularly important for the correct development of roots.