by Margie Siegal
If you travel on Interstate 5 through the Central Valley, you will see signs along the highway “IS GROWING FOOD WASTING WATER?” The answer is – it can be! If a farmer does not make the best use of the water that is available, the farmer is wasting water. The same is true of someone running a mini farm in their backyard. This year, it has only rained 40% of normal and East Bay MUD is talking about raising rates, so using the minimum amount of water needed for your garden might be a good idea.
Most vegetable crops do not need to get water on their leaves, and, with quite a few, wet foliage can lead to various diseases. It makes sense to only deliver water to the roots, which is the part of the plant that can properly utilize it. Experts suggest that most vegetables need two inches of water per week to flourish. There are various ways to deliver this water, including by using a hose, a watering can, or drip or soaker hose irrigation. Irrigation systems require an investment in both money and time to install them, but will pay you back by lowering the water bill and minimizing the time you have to be involved with watering while still keeping plants happy.
Sprinkler systems used for lawns are not good for vegetable gardens. Water gets on the leaves, a fine mist sprays into the air and evaporates, and the wind can blow water onto pathways. The water bill goes up and vegetables don’t get the water they need where they need it.
The cheapest way to irrigate is to get the kind of multi-spray hose nozzle that has a ‘soaker’ setting. Make sure the nozzle will stay on even if you are not holding it. The sprayer head should either have a lock setting or turn on and off by means of a lever. If you also get a manual timer, you can attach the timer to your hose, attach the nozzle to the timer, turn on the water, make sure that water is going where you want it to go, set the timer, and go off and do something else. This type of setup also works well for plantings that temporarily need more water, such as new trees.
The two most efficient water delivery systems currently available to the backyard grower are drip irrigation systems and soaker hose systems. These two types of systems each have pluses and minuses, and can be combined to produce the most effective watering system for your property. Getting water to your tomatoes and lettuce requires a ‘system’ because irrigation has several parts, all of which need to work together. They are:
A Timer
While a timer is not strictly necessary (you can turn the faucet on and off by hand) it has many advantages. Timers can be manual or electric (and require batteries) or electronic (sending data to your smartphone). You can get a timer with multiple dials that will water particular parts of your garden for different times. Timers range from $15 (for a simple, sturdy manual timer) to $160 for a Bluetooth enabled timer with multiple heads. Fancy timers sound expensive, but will pay for themselves in short order if you regularly go away for the weekend – no need to pay a plant sitter!
Large diameter hose to get water to one general area
Normally, the faucet (often referred to as a ‘hose bib’ in discussions of irrigation) is next to the house and the veggies are several feet away. There are also often several different vegetable beds in different areas of the yard. A timer with multiple heads or a “Y” that attaches to the faucet can be used to direct water to these different areas. Heavy duty drip line can be buried under pathways, to emerge where water is needed. Drip line tends to kink when bent. For gentle bends, cut a section of PVC pipe and slip it over the hose to keep it from kinking. For 90 degree bends, elbow joints are available.
Smaller diameter tubing or soaker hose to get water to each individual plant
Once the water is within a few feet of your plantings, use smaller diameter tubing to direct water to emitters or attach soaker hose to the large diameter line.
- Emitters weep water at a controlled rate onto the base of plants. They have a stake at one end and a valve at the other. The stake end is pushed into the ground and a small diameter tube is attached to the feeder line on one side and the emitter on the other. The instructions that come with the brand of emitters you buy will tell you how many emitters you need to water a given area.
- Soaker hose, which weeps water out tiny pores, comes in different diameters. Some types of soaker hose are about the same diameter as a regular garden hose. Other types are about a half inch in diameter and replace emitters. Soaker hose bends almost as easily as regular garden hose.
Each type of irrigation system has pluses and minuses. Emitters and the small diameter lines that feed them will get clogged over time and need to be monitored. The up front investment can be daunting. A simple soaker hose system is relatively inexpensive. Soaker hose will not clog. However, soaker hose does not work well on slopes, and needs to be closer to the plants than an emitter does. It is also difficult to repair if you accidentally stab it with a pitchfork.
With any type of irrigation system, the amount of water that is getting to your plants can be checked by putting a clean 14 ounce can under the point where the water is emitting and seeing how long it takes to fill the container one inch. Turn on the irrigation system twice this amount of time per week.
While an irrigation system, once installed, may not be quite ‘set it and forget it’ as claimed by the ads, (the system needs to be checked on a regular basis to make sure it is working properly) you will spend a lot less time out standing in your field with a hose, you will do your part to limit water usage during a drought, and your water bill may even go down.