Drip irrigation, aka micro irrigation, delivers water slowly to the base of plants at the soil line. With a 90% efficiency, water gets to where it’s needed with very little waste.
It’s said that water is our most precious resource. And in this era of climate change with record heat and drought, conserving water is critical. Growing fruits and vegetables requires a significant amount of water and while your Arborvitae and Rhododendrons may survive 3 weeks without rainfall, your tomato plants, lettuces, and blueberries will not.
But many gardeners waste water with improper watering methods: watering when it’s too hot; when the sun is too high; getting foliage wet (also a disease contributor); watering too fast; not mulching; and other mistakes. Drip irrigation can solve many of these problems, especially in arid and drought-prone areas where water may be in short supply.
Drip irrigation can be used for any plant in your yard or garden, including trees, but for this article, we’ll focus on your vegetable garden.
How drip irrigation works
Drip irrigation works by placing water slowly and directly into the soil—literally “dripping” it from small water emitters that are positioned at each plant or from an emitter line that is snaked around the planted garden bed. Drip is also an excellent method for watering sloped and terraced gardens because the slow rate of watering means it is more likely to soak in before it runs off or evaporates.
Benefits of drip irrigation
- Uses less water than a garden hose or watering can.
- 90% efficiency – only 10% of water is wasted vs as high as 50% with sprinkler systems and other watering methods.
- Easy to install.
- Customizable for any garden.
- Water is applied to the root zone only, reducing the threat of disease.
- Less weed growth, since only the target plant is watered.
The 3 components of a drip irrigation system
- The Head: including the water source, system control valve, filter, and pressure regulator.
- Distribution system: the hose or pipes through which the water flows.
- Emitters: devices inserted into the hose or pipes to deliver the water to your plants.
The head consists of a water source with a valve, a filter to remove fine particles from the water so the emitters won’t clog, and a pressure regulator to reduce the water pressure to under 25 psi (most city systems are between 25-60 psi).
The distribution system is the pipes or hoses that carry the water to the plants. Pipes are usually made from PVC or black polyethylene. Also includes connectors to adapt the hose or pipes to the emitters.
Emitters are the most critical part of your drip irrigation system. Emitters come in many different designs and are generally classified as point source, linear, or micro spray.
- Point source emitters are placed next to the plant and deliver water to its base. They are the simplest and least expensive. This is sometimes as simple as a small hole punched in the pipe or hose.
- Linear emitters are set in the tubing by the manufacturer and are best used in gardens where the layout doesn’t change, such as in a perennial garden to water shrubs.
- Micro-spray emitters spray a fine stream of water at the plant’s base. These can be installed directly in the tubing or on stands above the ground.
Buy on Amazon: Drip irrigation parts and systems
Is setting up a drip irrigation system complicated?
Drip irrigation in the vegetable garden doesn’t have to be a permanent installation unless you’re using the square-foot gardening method. Assuming you’re practicing crop rotation, you’ll be changing what and where you plant each year. Since next year’s tomatoes won’t be in exactly the same spot as this year’s, your drip irrigation system will have to be modified each season. So for the vegetable garden, be economical with your materials and stay away from a rigid configuration.
Drip irrigation systems can be as simple or as complicated as you see fit. But planning is crucial: before designing your system, you’ll need to know the water requirements of your plants and how to size the design to deliver the water where it’s needed with enough pressure. See the resources list below and the videos to learn more.
Drip Irrigation resources to get you started:
- UC Master Gardener Program of Sonoma County: Drip Irrigation
- University of Arizona, Cochise County Master Gardeners, Basics of Drip Irrigation
- Utah State University, Designing a Basic PVC Home Garden Drip Irrigation System
- Colorado State University Extension, Drip Irrigation For Home Gardens
- Treehugger: How to Create Your Own Drip Irrigation System