Hydro Growing for beginners: Rock wool, Coconut or Hydro granules?

Are you going to grow hydro for the first time? Hydroponics starts with choosing a good medium. Are you going to grow weed on rock wool, coconut fibre or hydro granules? And what does a drip system or deep water culture really mean? In this guide hydro growing for beginners we explain everything and together we'll look for the best hydroponic medium for you!

In this article:

What is Hydro Growing?

Hydro growing is also known as hydroponics and basically means growing on water. It is widely used when growing weed plants. With hydro growing your weed plant does not grow in soil, but in another medium such as rock wool, coconut fibre or hydro granules. You can directly start growing in one of these growing mediums, but you can also use a Deep Water Culture system or a drip system.

A hydroponic medium is very aerated. Partly because of this, the roots of your plants are continuously surrounded by water. This way, they can absorb oxygen and nutrients perfectly. The roots are given plenty of room to develop, allowing you to create enormous root systems that form a fantastic base for your weed plant. Are you going to grow hydro? Then in addition to a suitable medium you also need to use special nutrition. For every medium there is a special kind of plant nutrition. Growing hydro is, especially when you work with a drip or deep water culture system, quite difficult compared to growing on soil. Hydro growing for beginners? Read up on it before you start.

Deep Water Culture or Drip system for weed

Growing on hydro is not something you just do. Only an artificial soil such as rock wool, coconut fibres or hydro granules is not enough. At least, not if you choose deep water culture or a drip system. With these two systems, watering is continuously arranged for you. But what are these systems exactly?

A drip system speaks for itself. You can use it with rock wool, coconut, clay or hydro granules. Your weed plant then simply stands in a pot filled with this medium. The drip system constantly drops nutrition and water on the medium. Under the pots there is a water reservoir that collects the nutrient water, after which it can be used again. A drip system for weed is handy because your weed plants absolutely should never be allowed to dry when growing hydro. This is why growing hydro without a drip system is very time-consuming without automating it.

With Deep Water Culture your plants are also in a pot filled with rock wool, coconut, clay or hydro granules. However, the roots can easily grow through this medium. This is also the idea, because with deep water culture the roots of the weed plant are collected in a container with water and nutrients. The water is provided with oxygen by means of an air pump and/or bubbles.

Growing hydro and Police

Keep in mind that there is a lot involved in setting up this system and it will soon look as if you are engaged in professional cultivation. If the police comes to check whether you are following the rules, there is a chance that you will have to hand over all your stuff because it is no longer small-scale cultivation for personal use. Whether they are right or wrong does not matter. In many countries those are the rules for growing weed.

PH-value Hydro growing

With both deep water culture and a drip system, you need to pay very close attention to the pH, EC and nutrient values. You must measure this every day and adjust it if necessary. The pH-value is the acidity of the water. Also with other forms of hydroponics, keeping an eye on the pH-value is of vital importance for your plants. Also, the ideal pH value is different than when you grow in soil. In any case, make sure the pH is between 5.8 and 6.

You can also grow directly in a hydroponic medium. But this takes a lot of time, because you have to constantly make sure that the roots do not get dry. 

Weed on coco coir

Coconut Soil

Growing weed on coconut is fairly easy. You can do it with or without a deep water culture or drip system. Coconut potting soil has a number of advantages over other types of potting soil. This reasonably simple method of growing hydro is the closest thing you can get to growing weed on soil. Coconut potting soil is a very airy medium, leaving more than enough room for the roots to take in oxygen and grow. Because the root system can grow optimally your plant has a head start during the growth phase. This is one of the reasons why coconut is ideal for growing fast flowering strains. Coconut is also ideal for sustainable growers. You can reuse coco fibres. Grow finished? Put in a new one and go!

A great advantage of growing on coconut is that it is almost impossible to overwater your weed. This is because coconut soil absorbs far less water than earth. On the other hand, you do have to be careful that your weed plant does not get dry. Growing on coconut is a little more time-consuming because you have to water a lot. Is your weed plant standing dry for too long? Then it can quickly deteriorate and even die. So a drip system is certainly something to consider. It takes a lot of the work out of your hands.

Coconut potting soil and nutrition

Coconut potting soil itself does not contain any nutrition. Therefore, you are in complete control of your own nutrition and you have less chance of leaf problems and diseases. When growing on coconut you only need to use one type of plant nutrition during the entire growth. For example, . That is a balanced two-component nutrient. That is all you need. So no fussing around with stimulators, boosters and other additives. 

You can also choose to grow on 100% coconut fibre. This is a pure form of hydro cultivation. Coconut potting soil is often very expensive and you have to keep an extremely close eye on the pH and EC levels. A very suitable alternative is Cocos Brix from Plagron. This is a buffered and compressed lump of coconut fibre which expands considerably when water is added. With Cocos Brix you immediately have a pure, natural and pH-stable medium for your weed plant.

Want to know more about Growing weed on coconut coir? Read the extensive blog!

Coconut Brix from Plagron: buffered coconut potting soil

Clay Granules | Hydro granules

Hydro granules are extremely popular for hydro growing with weed plants. Hydro granules are actually just clay granules. They are available everywhere. Note that you sometimes have to adjust the pH of clay granules before you can use them for your weed plants. Clay granules hold a lot of moisture but offer less support for roots. This makes hydro growing with clay granules without a deep water culture or drip system almost impossible. Do you want to grow directly in a hydro growing medium, without any complicated systems? Then you should choose to grow weed on coconut. 

Hydro granules offer an extremely airy medium for weed plants. You put the clay granules in a special basket. The basket has holes through which the roots can grow. A richly filled water reservoir with special nutrients for hydro growing provides for the roots. Because the soil is so airy, the roots can grow freely and absorb oxygen. A fully grown root system when growing on hydro granules looks spectacular. 

Root system when growing on hydro granules / clay granules

Combining Weed Potting Soil with Hydro Granules

Hydro granules are also often used in combination with coconut potting soil or weed soil. This way you optimize the soil structure of the potting soil. By placing a layer of hydro granules under weed soil, you create a better drainage. The water you give your weed plants will no longer stick to the bottom of the pot, where it can become too damp and cause root rot. A layer of hydro granules makes the bottom layer of the pot nice and airy and prevents these kinds of problems. 

A combination of coconut fibres and hydro granules is considered one of the best types of potting soil for weed. A mix of 60% coconut fibres and 40% hydro granules, for example, is a well-balanced mix in which your weed plants can grow excellently. Yet even with this form of hydro growing you have to be careful. You need to water regularly and keep an eye on the pH and EC levels.

Growing weed on rock wool

This insulating material may not be the first thing that comes to mind when you think of a good soil, but rock wool makes a fantastic medium for weed plants. It is clean and it absorbs a lot of water. Therefore you can be sure that the root system of your weed is constantly hydrated. On condition, of course, that you give the plant sufficient water.

When growing weed on rock wool the roots are well covered. Partly because of this, it has an excellent buffering effect. This means that rock wool easily absorbs nutrients, protects them and evenly distributes them to the root system. Not to mention that it is extremely cheap! 

This medium also has its disadvantages. It is quite complicated, especially for the beginning grower. You have to take many factors into account and there is often a considerable growing schedule involved. You cannot grow on rock wool without a deep water culture or drip system. You have to put rock wool in the same sort of container as described above for hydro granules. Rock wool also has a relatively high pH value. So you need to rinse the rock wool well and check the pH-value during the growth. 

Growing weed on rock wool with a drip system

Conclusion: is Hydro Growing suitable for Beginners?

Let's get straight to the point: hydroponic growing is not suitable for beginner growers. It is better to grow on soil first, before you start hydroponics. That's because there are so many things to consider and complicated systems to deal with. Do you have experience with growing on soil or do you just want to try? Then you should opt for growing on coconut, since you can easily do that without a deep water culture or drip system. Do you like a little experiment? Then look for a deep water culture or drip system and choose to grow on rock wool or hydro granules. But beware of snitches or police visits. Such a system is a magnet for a fine or other consequences from the law. 

Want to grow on soil? Then read our blog 'The Best Potting Soil for Weed'. Here you can read about the requirements weed soil has to meet and learn how to make the best potting soil for weed yourself!