The Absentee Gardener: How to Water Your Vegetable Garden without Being Home
Keeping up with your vegetable garden in the heat of summer can be a daunting task, especially when watering by hand…Posted Aug 27, 2013
Who hasn’t cheated their thirsty plants when pressed for time, or arrived home after summer vacation to find nothing but crispy stalks remaining?
There are many reasons to install automatic watering in your garden, but none more convincing that the time saved and the freedom earned. Replacing both hoses and sprinklers with an easy-to-assemble irrigation system provides more time for you to do other things, like enjoy your garden (or your holidays).
Here are a few tips to remember when installing an automatic watering system in your vegetable garden:
1. Arrange your beds with irrigation in mind
Although it may be appealing to opt for sweeping curves or labyrinthine passageways when arranging your vegetable garden, remember that long, straight beds make for more economical watering. Lining up your beds in one or two directions is less expensive because it requires the least amount of equipment. Parallel beds with few paths between also maximize coverage from your system and minimize water loss.
Before planting your vegetable garden, think about where you plan to install automatic watering, now and in the future. Arrange those beds in long, straight lines and set the bed width according to your natural reach. (We find four feet a good width for a bed, but this will ultimately depend on the plantings, the length of your arms, and the type of watering system you choose.) The same rules apply when using raised beds.
2. Choose a simple watering system with minimal parts
However you design your vegetable garden, your automatic watering system will need a few key parts to make it function optimally. These include:
a) A main water line
The main water line or hose brings water from your water source directly to your vegetable garden. Sizes vary, but our favorite is durable, three-quarter inch tubing with enough flexibility to bend and enough resistance to withstand the occasional jab from a shovel. Standard ½” or 5/8” garden hose will also work.
b) Irrigation lines
With drip irrigation systems the thinner, more flexible tubing carries water from the main line to each plant or garden bed. Often drip holes will perforate irrigation lines (our favorite for traditional garden rows). Thinner lines may terminate in a water emitter, which is often desirable for raised garden beds (see below). A good rule of thumb is to calculate your garden’s moisture requirements per week and then design your system to deliver that volume. Irrigation line options include the very economical drip tape (which usually requires a pressure reducer) and the more durable drip tubing. Micro Drip Irrigation Kit (pictured left) is a complete drip-irrigation system ideal for planters, potted plants, hanging plants, and raised garden beds. MicroEase Sprinkler Conversion Kit is a more complete drip-irrigation kit for versatile drip systems in gardens and landscapes. Drip irrigation is especially compatible with berry bushes. We also use 2-3 lines of drip tubing per garden bed for most of our vegetables.
c) Water emitters
Install water emitters like drip spikes and micro-sprinklers on irrigation lines running perpendicular to your main line for plants with greater water requirements. We use drip spikes and “shrubblers” in our greenhouse to ensure tomato, fig, and cucumber plants receive water right at the roots. These emitters feed plants directly, leaving little on the soil surface to evaporate.
Every part in your irrigation system connects to every other part with a coupling or connection. Changes in tubing size, direction, and type require these handy, waterproof transitions to ensure the water will end up where you want it. Most irrigation systems now come with a simple punch tool that makes connecting the parts simple. We’ve also found a thermos of boiling water is excellent for softening hose tips prior to inserting hard plastic connectors. Connections are also required between tubing and emitters like bubblers and dribblers.
e) Filters and valves
Installing a filter between your water source and irrigation lines will help prevent clogged emitters, especially if your garden water comes from an unfiltered source such as a lake or pond. Using valves at various places in your garden also gives you more control. In retrospect, we should have installed shut-off valves to allow the greenhouse to operate independently from the rest of the watering system. Instead, we now hand-water the greenhouse during those rainy weeks when everything else is wet, or risk turning on the whole system when it doesn’t need watering. This is something we will remedy in future adjustments to our current system.
A reliable timer is the heart of your watering system. Although today’s timers offer enough functions to overwhelm, all you really need is something that you can program to run the water for the duration of time you need. (However, no matter how easy it seems, we still advise reading the manual.) In the heat of summer, we set our timer to water every two days, from two o’clock until six o’clock in the morning. In that time our system is active four times for thirty minutes each—a total of two hours watering time. Watering in the wee hours guards against evaporation and delivers water to the plants when they are drinking the most. Spacing out our watering in intervals also allows our well time to adjust and recover in the driest part of the year. This watering pattern is not something that would ever get done by hand, given that we like to sleep at night.
3. Maintain your system
Once you have your system in place, a simple maintenance schedule will ensure it functions for years to come. We perform the following routine checks to ensure our plants continue to receive the water they need with little help from us:
- Clean the filter on a regular basis to ensure optimal flow.
- Check soil wetness at rooting depth and plant condition to adjust watering amounts and frequencies.
- Check timer battery and replace as needed.
- When your garden is dormant, drain water lines by blowing water out with an air compressor in areas subject to freezing weather. You can also drain the line by opening the lowest part and letting gravity do the work. Level sections may need to be opened at some point in the line to allow for expansion during hard freeze ups in winter.
- Check for leaks and blocked emitters when starting your system up at the beginning of the season and on a regular basis.
4. Adjust and expand as needed
Gardens are always evolving, and water needs may change as the garden expands and as crops are rotated. Drip irrigation systems are designed to be easy to expand or adjust as needed. Lengths of tubing can be added to the line at any time, even after the initial installation is complete. If you add another bed or row, or if you want to remove the line from a bed, the components can be readily unclamped. For example, “T”s in the line which split the water flow can be replaced with “unions” which return the water flow to a straight continuous line. Emitters can be removed and the hole plugged, and new emitters can be added with the punch tool anywhere in the line. A screwdriver is needed to release the steel hose clamps, but otherwise most adjustments can be made without the need for special tools.
After three properties and three irrigation systems, we are pleased to have found something that functions smoothly with little upkeep. The freedom these systems offer far outweigh the time it takes to install them and their upfront cost. Our present garden agrees: now in its second season with automatic irrigation, it has never looked better.
Shannon Cowan is a writer and editor whose novels and articles are published in the United States and Canada. She and her family are currently building a green home and converting six acres of semi-rural brush into a working farm. She blogs about their adventures at www.agreenhearth.com.