Last updated on October 23rd, 2023 at 08:57 pm
Hydroponic sounds very remote at first and seems even more spacey on closer inspection: growing plants entirely without soil. To some, this will seem very unnatural, but it has real advantages for the plants and for the environment.
On this page, the advantages and disadvantages of hydroponic cultivation are briefly described and various systems are presented.
1 Wicking aka wicking system
In wicking, the nutrient solution is located below the plants in a vessel. The substrate, an inorganic material in which the plants are rooted, and the nutrient solution are connected by a wick that directs the solution upwards. However, it does this in relatively small quantities, so this system is mainly suitable for plants that have a low water requirement.
So far, the wick system is a purely passive system for irrigation. But it is often supplemented by an air pump. This adds oxygen to the water, which can be absorbed by the roots of the plants. With this system, an unforeseen failure of the pump is not tragic. This is because the roots are not suspended in the water here, but in the loose substrate, so that sufficient oxygen can still reach the roots.
- Advantages: The system is not dependent on the functioning of a pump.
- Disadvantages: It is only suitable for plants with low water requirements.
Plants grown in hydro develop water roots and cannot be transplanted into soil. In soil, the roots usually rot away.
2 Water Culture
In water culture, sometimes from Deep Water Culture (DWC), the roots of the plants grow directly into the nutrient solution. The plants themselves are housed in pot-shaped nets so that they are held but the roots can grow into the nutrient solution without much resistance. The plants remain above water through a floating plate, such as Styrofoam, from which holes have been cut for the pots.
The water in this system must be oxygenated by an air pump, because the roots have no way to get air. Without the air pump, the roots would rot away and drown, so to speak.
- Advantages: The system is simple to implement.
- Disadvantages: It depends on the functioning of the pump.
3 Ebb and flow systems
In the ebb and flow system, the plants are placed in a container on a substrate. Below the container is the reservoir, which is connected to the container by one or two pipes. At flooding time, a water pump pumps the nutrient solution into the container until a certain water level is reached. Then the pump switches off and gravity causes the remaining nutrient solution to run back into the reservoir. It is low tide in the container. So the plants can be flooded several times a day.
- The plants are not constantly in the water.
- The oxygen supply to the roots is guaranteed, because the inflowing water displaces the “exhaled” air and fresh air is attracted by a slight negative pressure when flowing out.
- The ebb and flow system is highly dependent on the water pump functioning properly.
- The water hoses can become clogged.
- A timer to regulate the watering cycle is necessary.
4 Nutrient Film Technique (NFT)
Nutrient Film Technology is mainly used in greenhouses for commercial cultivation. The plants are usually placed in net pots, which are in turn placed in a tube. A constant flow of nutrient solution flows along the bottom of the tube. For this purpose, the tube is placed on a slight slope. At the end, the solution flows out again and back into the main reservoir. Here the solution is oxygenated again by an air pump and an air stone and finally pumped back into the tube. So the water is constantly circulating through the system. The roots of the plants hang only with their ends in the solution, their majority is free and can thus optimally absorb oxygen.
- This system is also dependent on the functioning of the pumps.
- If water does not reach the freely hanging roots, they will dry out quickly because there is no substrate that could store water.
- Through NFT, many plants can be supplied at the same time.
- They are easy to reach, harvest and change.
- Plants growing further back in the nutrient solution stream potentially get fewer nutrients.
5 Drip Systems aka Drip Systems
In a drip system, a water pump pumps the nutrient solution through a pipe from the reservoir to each individual plant. The unabsorbed water flows back into the reservoir by gravity through a drainage system. Thus, it is a closed circulating system. The interval of dripping is usually controlled by a timer.
It is advisable to place an air stone in the reservoir and use an air pump, although oxygen reaches the roots through the substrate, the grow result is significantly improved by more oxygen.
In general, the Drip System is not necessarily hydroponic, but conventional soil can also be used as a substrate. Rather, it is an irrigation technique, as it is often used in gardens and balcony plants in more southern climes. The difference, however, is that here the water not absorbed by the plant usually simply seeps into the soil, while in hydroponic systems, where possible, the water is collected back into the reservoir.
Advantages: The drip system is also well suited for large plants.
Disadvantages The system depends on the functioning of the water pump.
The name aeroponics is derived, among other things, from the Greek word for air. In this system, the roots of the plants hang freely in the air, which gives them plenty of oxygen.
The plants receive nutrients through a constant spraying of nutrient solution. The solution itself is in a reservoir, from which it is pumped to the spray heads. The spray should be as fine as possible to ensure oxygenation of the roots.
- The method allows very fast and vigorous root growth.
- Requires the least amount of water compared to the other systems.
- The nozzles of the spray heads can be easily clogged by the nutrient salts.
- The system is extremely dependent on the pump, as no substrate can store nutrient solution to bridge short periods.
Benefits of all Hydroponics Systems
- Less water and nutrient consumption
- Hydroponic cultivation is much more efficient than conventional cultivation with soil. The nutrient solution reaches the plants directly. Oxygen reaches the roots through the loose substrate.
Due to the closed system, water does not evaporate and it is not bound by soil. The water with nutrients not absorbed by the plants is recycled. This minimizes consumption, also good for the environment.
Select the nutrients yourself
In hydroponics, plants are supplied by a nutrient solution. This gives the gardener full control over the amount and composition of nutrients and makes it possible to adjust them as needed. Herbicides are eliminated by hydroponics, and without soil, fewer animal pests are attracted as well.
Initial cost and payback
Hydroponic systems are quite expensive to purchase, but in return, water use is minimized and yield is maximized, and fruiting is achieved in less time. Thus, a hydroponic system pays for itself with long-term use.
However, it also requires some know-how on the part of the grower. The faster plant growth makes more care and maintenance indispensable.