Passive hydroponics or wick irrigation systems, which are often called ?aquatic culture?. The ?passivity? implies that the system is not equipped with a pump, but works due to the capillary forces of the wick which raises the nutrient solution from the tank to the root zone. This method has been used in flower shops and nurseries for the cultivation of indoor plants for quite a long time. Such systems perfectly support for some time the life of slow-growing ornamental plants in pots with soil. Their use allows you to maintain the optimum moisture content of the potted soil due to the capillary mat or wick. These excellent systems provide full automatic moistening for two to three weeks with an adequate supply of water.
In the case of wick irrigation of plants placed in an inert substrate, capillary forces will not be enough to moisten the root system in felt pockets. For healthy plant nutrition, mineral salts are added to the water, which, quickly settling on the mat or wick, dry out and block the capillary effect. Water circulation almost stops. Such a system is completely unsuitable for growing fast-growing plants that need plenty of water. It is more an ingenious device for home use than a serious system of cultivation of plants. The principle of operation of this hydroponic system is to place the plant in a container that is filled with an inert substrate. The lower third of it is separated by a partition and filled with water. Cotton is usually used for the wick, but synthetic fabrics are better. It is placed in the upper part and hangs down through the hole in the compartment with water. The capillary effect allows water to rise through the wick and supply the roots with moisture. There is a more effective type of system in which the slits are located along the entire perimeter of the partition. Of them, a capillary mat is lowered into a container with water.
There is also another, noteworthy ?passive? system. In contrast to the previous one, this system grows very good plants, but at the expense of the wasteful use of water and nutrients. It is enough to fill ordinary pots with an inert substrate, place them on a seedling table with a drainage hole or in any place where excess water can be drained. Irrigate plants with nutrient solution. Between irrigation sessions, the substrate should almost dry out. It seems that everything is simple and cheap in execution, and the plants are large. The hitch is that between each irrigation the pots have to be rinsed with a large amount of water, which leads to very uneconomic water consumption. According to the norm, the pot needs to be rinsed with a volume of water at least twice the volume of the pot in liters. This is necessary to get rid of the mineral salts precipitated during the drying of the substrate. And the substrate must be allowed to dry so that oxygen penetrates into it! This is also a wasteful use of nutrients. In this case, not only salts are lost, which are washed out, but also when irrigating the plants, irrigation water is poured out in order to surely dampen the entire root mat.
This method is somewhere on the verge of hydroponics and non-hydroponics. Fill one pot with an inert substrate and the other with the earth. If you photograph them side by side, they will look exactly the same, but one of them belongs to hydroponics, and the other does not. Apart from the fact that this method is unfavorable environmentally, it is also burdensome ? because nothing can be automated. Your presence is required at least every other day for service. And often you have to carry water in buckets, which is always problematic in a confined space. However, some people most prone to masochism use this system and pray for it. What is true, it is true ? the system is practically protected from a fool. It gives results, but at what cost!
You should not try to use such a system for growing insatiable fast-growing plants! This system is more from the field of ingenious devices than cultivation methods. If you want to enjoy all the benefits of hydroponics, you will need a nutrient solution, distilled by a pump that dynamically and constantly maintains the level of oxygen in the water.
Free Expert Advice for Growing Vegetables and Fruits Hydroponically - Questions and Answers