Drip Irrigation Resources

Selecting the Right Irrigation System for your Home Garden

Micro irrigation is a low-pressure, low-flow-rate type of irrigation that can reduce the likelihood of overwatering a garden. This form of irrigation delivers water directly to where it is needed most -- the root zone of plants. It also delivers the water slowly and over a longer period of time, preventing runoff and reducing evaporation. Micro irrigation systems use up to 50 percent less water than conventional sprinkler systems.  Drip irrigation is one of two types of micro irrigation:

1.       Drip Irrigation: allows water to drip or seep onto the root zone

a.       Porous Pipe (soaker hoses)

b.       Drip emitters (Drip lines, Drip Tape)

2.       Micro-sprinklers: direct water into the air much like a miniature sprinkler head 

In general, soaker hoses and miniature sprinkler head systems are more suited for closely spaced plants. Drip emitters are best in situations where plants are more widely spaced, or in separate containers.  

The two types of drip irrigation systems on display at the Teaching Garden are 1) soaker hoses and 2) drip tubing with pre-installed emitters.

Soaker Hoses

A soaker hose is a porous tube that looks like a garden hose, except that it ‘weeps’ water along its entire length. Placed on the surface of your soil, soaker hoses deliver water steadily to your plants. Most soaker hoses are made from some combination of rubber and polyethylene plastic, but some BPA-free, polyurethane hoses are now available.

Soaker hoses work best for smaller gardens on level ground. In most cases they come with an inexpensive start-up cost and are easy to install and configure by snaking around plants. They work very well in raised beds.

Pros for Soaker Hoses:

• reliable water delivery at ground level, keeping the foliage on plants dry

• easy to install: simply hook up to a faucet or rain barrel and snake around the plants you want watered

• low up-front investment 

• can be moved from place to place in a matter of minutes

• work well on timers to further conserve water

Cons for Soaker Hoses:

• not possible to control pressure along the hose so high areas and locations near hose end get less water

• not possible to close off sections while allowing others to remain open as with drip emitter systems

• susceptible to clogging -- can be diminished by using a fine filter if mineral content in water is high

• radius of coverage is not as broad with soaker hoses vs drip emitter systems

• less precise watering than drip emitter systems

• can develop kinks, although double-walled soaker hoses have largely solved this problem

• if damaged, it is more difficult to repair a soaker hose than drip emitter systems.  

•  sun damage and degradation can take place over time (can be avoided by covering with a light mulch)

Drip Emitter Systems

Drip emitter systems are long tubes fitted with emitters. These systems work best in larger gardens configured in long, straight rows. Their versatility makes them a good choice for gardeners dealing with sloped ground.  Drip emitter systems consist of two main categories:

1. Drip tape:  This flat-style tubing requires a pressure reducer in the waterline to function optimally. It works well for subsurface installations, but isn’t usually manufactured to last more than a few seasons.
2. Drip tubing: This round tubing is manufactured with heavier duty plastic (usually polyethylene) that will function well for multiple seasons. You can purchase drip line with pre-installed emitters (best for crops planted at regular intervals) or separate emitters that you install yourself (ideal for customized spacing).

Pros of Drip Tubing :

•  deliver water directly to the base of your plants, so little is misdirected or lost to evaporation. Since they generally water slowly, over a long period of time, the water penetrates over a broad radius and deep into the root zone.

• you can configure the system to target certain areas of the garden while preventing flow to others, making drip emitter systems a good choice for large gardens with areas that remain fallow early or late in the season.

• you can install pressure-compensating emitters to ensure all areas of your garden receive equal amounts of moisture, no matter how hilly.

• you can choose customized emitters to work with your garden’s soil type

• if you inadvertently stab part of your drip system with a digging fork, it’s easy to repair and reconfigure by purchasing replacement parts. Splicing and fixing usually requires no specialized tools.

• work well on timers

Cons of Drip Tubing:

• emitters can become clogged over time, requiring periodic inspection and some maintenance

• wind can misdirect moisture from drip line, wasting water and missing the desired ground area to be wetted

• drip emitter systems usually involve a healthy up-front investment

• takes more time and planning to set up

For most people, choosing an all-inclusive garden bed irrigation kit is ideal.  Kits are available at most DIY stores, hardware stores or on-line from garden supply companies.