Best soil for growing legal hemp
When deciding to grow legal hemp, selecting the best soil is key in order to ensure that the plant can grow in an optimal way.
I will now explain what aspects you should look for in soil for growing legal hemp in the best possible way, also giving you a few tips on how to prepare a suitable soil on your own.
First of all it is important to say that not all hemp requires the same type of soil: the choice of the ideal soil depends on many factors, including the genetics of the plant you wish to grow, the climate, the growing environment, and whether you will grow indoors or outdoors.
However, there are some key factors to take into account and it is from these that we will start with our explanation.
Hemp soil characteristics
Let’s begin by talking about consistency, which should be as light and airy as possible to favour legal hemp growth, so that the roots develop in the right way and get the right amount of oxygen, which are key factors for a healthy and thriving growth.
However, this soil must possess excellent draining properties: this is essential in order to allow water to penetrate into the ground in the best way possible, avoiding stagnation, which could be very dangerous for the health of the plant, since in some cases it could even cause its death.
Water retention, that is the soil’s capability of retaining water, is also important for hemp: a soil suitable for its cultivation should be balanced between drainage and water retention.
Now let’s talk about soil pH, which is very important: in fact hemp grows and thrives only within a specific pH range. The level deemed perfect for hemp is around 6, although values between 5.8 and 6.3 are fine, as long as you don’t deviate too much from this range, otherwise you won’t get a high-quality yield; if the values are too far off, the plant will die.
The last element required by soil is nutrients: hemp requires a lot of nutrients to grow and thrive; in this regard, however, it is important to note that commercial potting soils are already supplied with all the necessary nutrients, which you may have to add when your plants start to bloom.
If, on the other hand, you are growing without nutrients, then the soil must be supplemented with organic molecules such as compost, vermicompost, humus and guano; the micro-organisms present in the ground will then transform these substances into nutrients that can be absorbed by your plants.
Speaking of consistency, it is worth noting that soil mixtures on the market are already fitted with all the required characteristics, but the case is different if you decide to grow hemp organically.
There are four types of natural soil: sandy, silty, clayey and muddy; however most soils are a combination of these, in different proportions.
The consistency is a very important aspect: clayey soils, in fact, are made of tiny mineral particles, capable of slowing down water drainage and thus root penetration, but they retain water well and are rich in nutrients.
Sandy soils, on the other hand, allow roots to penetrate better, however they retain little water, therefore they must be watered frequently. They provide good drainage and are fairly good for growing hemp.
As for the muddy soils, they have good water retention and good drainage and, thanks to the abundance of nutrients, they are among the most fertile soils.
Silty soils, on the other hand, are perfect for growing hemp: being made of sand, clay and silt, they are porous and provide good drainage, retaining nutrients beneficial to the growth and development of the plant. They are therefore rich in oxygen and nutrients, but have the drawback of being very expensive.
If you grow hemp in a natural soil, it is recommended to add the so-called “soil conditioners” to improve your soil quality, which are quite easily accessible on the market.
Let’s see which ones are the most recommended for growing legal hemp.
Coconut fiber, which is obtained from coconut shells, provides lightness to compact soils and offers a virtually perfect water retention; it is advisable to add up to 30% coconut fiber.
Then, there is expanded clay, which is widely used in hydroponic cultivations, but it is also very suitable for growing in the soil, as it increases drainage capacity, preventing stagnation which can lead to plant rot; it is also capable of retaining the right humidity and protecting the plant from atmospheric agents, at the same time helping to prevent infesting weeds.
We also recommend using perlite: it is the most widely used soil conditioner, and it improves drainage and airiness, while also providing water retention that should not be underestimated; however, it is advisable to be careful with the doses, because if you overdo it, you risk to make the soil too light, thus resulting in nutrient dispersion.
Among soil conditioners, we also find vermiculite, which is a mineral that has good capability of lightening the soil, also increasing water retention; we could say that it serves the opposite purpose to perlite, which we mentioned earlier, yet both soil conditioners can be used at the same time.
Let’s also talk about vermicompost: it is good for improving drainage and water retention, providing at the same time plenty of nutrients, thanks to the presence of beneficial microorganisms.
Ready-made or homemade potting soil
If you just started growing legal hemp, the best advice we can give you is to buy ready-made potting soil from a specialty store: since these are hemp-specific mixtures, they contain the right nutrients and present the proper balance; at the very least, we recommend adding perlite to improve drainage.
Most people prefer homemade versions, also because they are cheaper than ready-made mixtures.
Now we will share with you a basic recipe for preparing potting soil for both indoor and outdoor planting: you need one part of coconut fiber, one part of vermiculite, two parts of compost and half cup of vermicompost.
To prepare this soil you need to sift the compost and remove the larger residues, then soak the coconut fiber in hot water; then mix the coconut fiber with vermiculite and lastly with compost. The potting soil is now ready, you just need to measure its pH, bearing in mind that the ideal values range from 5.8 to 6.3.
To this you can then add organic fertilizers, such as bat guano, which has the benefit of being particularly cheap; you can mix it with the potting soil or spread it on the surface and then water.
Soil conditioners helpful in case of drought
Now let’s consider the case of growing legal hemp outdoors, perhaps in sunny and very hot climates: if you grow in pots, the best idea is to choose light-colored pots, to help the soil maintaining the right humidity; it is also very convenient to use a layer of straw at the bottom of the soil, to prevent temperature changes.
Should your areas be very dry, then you can consider using absorbent polymers to keep the soil hydrated. You can find them in specialty stores; just lay them on the bottom of the pot before planting the hemp and then water it.