Capillary irrigation system

What is a capillary irrigation system?

A capillary irrigation system is a method of irrigation where water is supplied to the plant from a water source located in or below the base of the plant bed, using the capillary effect of the medium.

Capillary irrigation systems are efficient, produce higher yields and use less water than conventional irrigation methods. In addition, capillary irrigation provides the additional advantage of reducing the amount of potentially harmful effluents into the surrounding soil environment. However, these systems are generally limited to small pots and are widely used for growing ornamental and nursery plants in greenhouses.

Gravity and capillary irrigation

Depending on how you look at it, irrigation methods can be divided into two: gravity irrigation (irrigation from above) and capillary irrigation (irrigation from below). Each has its place in gardening and both methods can be used successfully.

Capillary irrigation

Includes irrigation from below or other systems that rely on the effects of irrigation. The soil can be irrigated without watering it from above. This is achieved by capillary action. Water rises slowly, despite the force of gravity. The molecules attach to the soil particles and rise through the tiny air chambers to the soil boundary. This ability of water to rise vertically can be observed in nature, and we can imitate it in design.

What happens to gravitational water that falls as rain? Some of it flows into streams and rivers. However, some water penetrates deep, even beyond the reach of plants. Such water enters the groundwater. Groundwater is where water collects in open pockets beneath the Earth's surface. These aquifers are the source of natural springs and wells. Some of this water even rises up and supports well-rooted perennials. This basic behavior of soil water can support trees during drought.

Watering from above

A water supply system that transports water thousands of kilometers before gravity eventually pulls it down and onto our thirsty garden plants.

Gravity irrigation Water is applied above the surface or soil line. Depending on the structure and density of the soil, there are certain air pockets or spaces between its particles. As gravity pulls water down, it travels between these spaces and saturates the soil. Different soils can hold different amounts of water. The rest of the water is held by cohesion and adhesion. Adhesion describes the tendency of water molecules to stick to each other. Adhesion causes these molecules to stick to other particles (such as soil).

Just as rainwater infiltrates the ground from above, there are many artificial systems that achieve the same effect. Drip, sprinkler, and canister irrigation systems also rely on gravity to pull water down to the plant's roots.