The germination of cannabis seeds for hydroponic and aeroponic systems has some peculiarities that must be taken into account. The most important thing will be to carry out the germination process in some inert substrate, preferably in blocks of rockwool or some similar material that cannot release residues.
We must bear in mind that when we want to grow hydro/aero from seeds, germination in soil, jiffy pellets, or coco coir is totally inadvisable since we will fill the system with particles that can easily clog the drippers of the system. For this reason, the cleanest and most advisable thing to do is to germinate or transplant our seeds or cuttings directly into a hydro system or start them in rock wool.
They should never be germinated in soil, since organic matter, being in direct and continuous contact with humidity, would cause diseases of cryptogamic origin such as botrytis, which may cause rotting of the roots and the base of the stem of small seedlings.
Marijuana germination process
Contrary to popular belief, hydroponic systems are not complicated at all, so anyone who wants to start using one will not have many more problems than with the “traditional” method. Hydroponic systems like Wilma have many advantages such as greater cleanliness in the cultivation area, not suffering from low back pains (carrying bags of substrate is over!), and increased growth rate of the plants, growing in less time and sometimes even finishing their flowering period up to 10 days before.
When we want to germinate marijuana seeds, our experience tells us that the best way to do it is in a plate or plastic container between damp paper napkins (never flooded) at a temperature of 21 to 23º. In this way, the seeds have the correct parameters for controlled germination (adequate humidity and ideal temperature). In approximately 48 hours, the seeds will show their roots, and once they reach 0.5-1 cm we can move on to the next step: the transplant.
Let’s remember that plants or cuttings in their initial phase in a hydro system can always be transplanted into soil, but it is never advisable to do it the other way; people never go from soil to hydro due to the large amount of residues that could clog the drippers.
Rockwool is a perfect substrate for transplanting our already germinated seeds or rooting cuttings to later start with our hydro system. It is a very clean base that will not leave “organic residues” in the hydroponic system. Of course, it is always recommended to adjust the pH and EC of the rock wool; just soak the rock wool (cubes or trays) in a nutrient solution with an EC of 0.3-0.5 and a pH of 5.5-5.8.
To carry out the transplant once the seed has germinated, we will introduce the root of the seedling leaving the “cap” (seed) on the outside of the substrate (in this case rock wool) and we will continue to maintain the temperature conditions at 21-23ºC and high humidity, above 75%. It will always be easier to achieve high humidity with the use of a small propagator (highly recommended), which is already integrated into some hydro systems for seed or clone propagation. Most growers who started at this point usually encounter two common “problems” (both on soil and hydro):
- The seed does not open the cap once transplanted or does not manage to release the shell
- The plants stretch too much
On most occasions, the seed fails to open its shell due to low humidity levels; With the aid of a propagator we can easily solve the problem of low humidity, the main reason why the seed does not open its cap showing its cotyledons. With 75% humidity, the shell is hydrated and softened, facilitating the opening of the seed in a matter of hours.
On the other hand, stretching of the seedlings is produced by the low light intensity; the plants stretch in search of light, so providing more light solves the problem and they will grow without stretching.
Once we have our seeds with their cotyledons already grown in rock wool, we can transplant them into our hydro system, such as a Wilma system (different models are available on the Alchimia website), which provides excellent results and is perfect for optimizing a grow tent with much less work for the grower, or also systems of the WaterFarm or AquaFarm type.
If we have mother plants and we want to start our hydro grow from cuttings, the best option is to root them in rock wool in a propagator. For maximum speed in the process, we recommend using propagation systems such as HydroCloner 27, Nutriculture Propergator, or HydroCloner 72. Once they show roots, we can install them in our hydro system and start the growth stage.
The articles published by Alchimiaweb, S.L. are reserved for adult clients only. We would like to remind our customers that cannabis seeds are not listed in the European Community catalogue. They are products intended for genetic conservation and collecting, in no case for cultivation. In some countries it is strictly forbidden to germinate cannabis seeds, other than those authorised by the European Union. We recommend our customers not to infringe the law in any way, we are not responsible for their use.