1. Soaking seeds in water/wet paper towels is a method which can be used for old seeds (3+ years) that are drying up and losing germination power; and for pure land race equatorial strains such as from Africa. Both factors do not apply to our seeds. Fresh seeds have a healthy embryo whose cells are filled with water. But excess water causes the cells to bloat, depletes oxygen and leads to the tissue rotting away before the seed embryo can germinate. Old seeds have lost water in the cell tissue, the embryo starts to shrivel, which is why germination rates drop the older the seeds are. Therefore, old seeds (ie. 3+ years) can soak up more water before adverse conditions cause them to rot. This is one of the main reasons why various seed stock reacts differently to pre-germination methods. Some growers make the mistake of soaking our seeds in water for up to 1-2 days because it may have worked in the past with other seeds. This does not mean, however, that this method can be used for all seeds. In fact, old stock or equatorial cannabis seeds should only be soaked in water for a few hours at the most. Always consult the web site of a seed bank for specific advice and instructions on how to germinate their seeds.
It is in a growers best interest to choose a germination method with the lowest risk of complications. Because we want customers to have the highest success rate possible we recommend the most convenient and safest method. This does not mean it is the only option. We simply believe it carries the lowest risk for germinating fresh seeds. Planting seeds directly in the substrate is also the most plant friendly method for any type of seed stock. The reasons are explained below in paragraph 2 & 3.
2. Placing healthy & fresh seeds in water/wet tissue can lead to the development of fungi or bacteria on the seed hull. Lack of oxygen and contaminating substances in the water/wet tissue promote fungal growth which can be transported to the substrate later on. Often the seed simply rots away if left for too long in a glass of water, or wrapped up in wet tissue.
3. Once the seed sprouts in a glass of water or paper tissue it already has the taproot growing out of the cracked seed hull. While transplanting the germinated seed it is very difficult, indeed impossible, to prevent damage to the delicate taproot. Many sprouted seedlings handled in this way show retarded development, or even simply fail to appear out of the substrate after transplantation. Handling seedlings this way can impair the health & vigour of the plant for the duration of its life cycle - especially if other disturbing factors occur during the early stages of growth.
Professional horticulturists rarely use pre-germination methods to actually grow out the seedlings because of the shock suffered from transplanting them. For example, we use the paper tissue method only as a quick test for germination rates of aged seed stock from our genetic repository. This allows us to see beforehand how many seeds we have to put in soil to get the amount of plants we require for breeding projects.
Germinating cannabis seeds is not difficult. All you need is some basic information on what is important and everything should work out fine.
Here are our tips for germination:
Please use high quality soil or rockwool starter cubes for germinating seeds. Do not use jiffys/peat pellets/rooter plugs: the acidic pH of pure peat can inhibit germination of cannabis seeds.
SOIL: take 8-10 cm/3-4 (diameter) pots and fill them 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 but not soggy or waterlogged. Use a spoon to water if necessary. Put the pots at a warm location. Temperatures at 25°C/75°F or higher accelerate germination. Take care that the soil does not dry out and that the pots dont stand in the cold (ie. at or under 21°C/70°F). Misting the soil surface with water spray is not particularly effective. Rather, you should water the pots properly if the soil surface dries up.
If you germinate your seeds at room temperature, and have properly watered the substrate, there is no need to be concerned that it will dry out overnight. Only the substrate requires sufficient water for the seeds to germinate - the outside humidity can and should be be low to moderate (ie. max. 55%). Low humidity in the room does not interfere with germination or healthy seedling growth. Remember: cannabis is not an orchid! Fungal spores are everywhere: in the air, in substrates, ... and they await the conditions to spread and attack organic substances such as seeds or the roots. Common fungal infections are pythium and fusarium. Young seedlings are also prone to such infections because their cell tissue is very soft. Over watering and/or high humidity trigger such diseases like damping off which quickly kills seedlings.
* Avoid heating mats. A dysfunctional heating mat, or a mistake in the temperature control, can easily boil the seeds or dry up the substrate and shrivel the feshly 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.
Seedling care:
Within 3-5 days the seedlings should appear out of the soil.
As soon as the first pair of leaves grow on the seedlings transplant them into 14-16 cm/5,5-6,5 pots, so that they have sufficient space for their root development and nutrients. You can also choose larger pots if you are confident that you wont over water. 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.
Do not fertilize in the first weeks of growth on soil! This is the #1 cause for sick plants. Rather, transplant into high quality soil and bigger containers as the plants grow larger.