Types of Irrigation Systems for Nurseries

Overhead Sprinkler Irrigation Systems

• Gardeners using overhead sprinklers typically have two options. The first option, rotary sprinkler heads, contain a rotating nozzle that sends a torrent of water over plants. The second option, stationary sprinkler heads, sends a rapid flow of water against a plate. The impact disrupts the steady stream of water, turning it into a continuous spray that waters plants.

  Although overhead sprinkler systems are the most common option in nurseries, they are not very efficient. They require high pressure pumps that consume large quantities of energy and fuel. Overhead sprinklers also waste about 80 percent of the water emitted. In nurseries containing plants with large or broad leaves, these plants encourage water waste when leaves redirect water away from plant containers rather than into the soil. Some gardeners compensate for water loss by installing slanted plant beds that channel water into ponds where it can accumulate and be recycled back into the nursery, although this may also recycle bacteria, sodium, fertilizer or pathogens as well.

Microirrigation Systems

• Unlike overhead sprinklers, microirrigation systems are highly efficient and can function using low pressure. However, soil, algae and chemical fertilizes can clog emitters. Three types of microirrigation systems are used in nurseries. One type of microirrigation, known as the capillary mat system, uses tubes that carry water into a mat. The mat becomes saturated with water, providing containers sitting on top of the mat with a supply of water to soak up through plant root systems. Although capillary mat irrigation uses 60 percent less water than conventional overhead sprinkler systems, they can cause salt accumulation in the soil over long periods of time.

  The second type of microirrigation system is known as a microsprayer, microsprinkler or spray stake system. Considered one of the most efficient nursery irrigation systems, microsprayers use a tube to carry water directly into the soil from a water source. Not only does this eliminate water waste that is deflected off broad plant leaves, microsprayers carry water directly to the plant's root system. Although microsprayers cost more than overhead sprinklers when installed in small plants, they operate efficiently in larger plants with more foliage and heavier canopies.

  The third type of microirrigation is known as the spaghetti tube system. This nursery irrigation method uses narrow tubes to bring water into the plant container. A miniature weight at one end of the tube ensures that it stays in the container. Water travels from one pore to another, through a capillary system. Consequently, gardeners must use a high quality, uniform soil for maximum efficiency. When using the spaghetti tube system, gardeners should keep soil moist at all times; dry soil will lead to poor water distribution.

Capillary Sandbeds

• Unlike sprinkler and microirrigation systems, capillary sandbeds do not involve any electricity. Containing wood panels, a plastic liner, sand, a small water reservoir, drainage pipe and valve, capillary sandbeds are built to slant slightly, allowing water released into the raised end to slowly travel to the lower end. Providing an even and continuous water supply, capillary sandbeds involve less maintenance. Plants grow evenly, relying less on fertilizer and pesticide. However, capillary sandbeds do attract weeds. Gardeners can purchase products to reduce the occurrence of weeds or they can remove them manually. Capillary sandbeds also have high installation costs.