Home & Garden

Gardening: Seven steps to the water-wise garden

gardening by Anna Thurston, Water Conservation Specialist for Tacoma Public Utilities
After a rainy winter, thinking of drought seems impossible, but now is the time to plan a water-wise garden. Because saving water simply adds up to good landscaping practice, gardeners are finding new techniques that can be applied to any garden.
   You might not even be able to see a difference in your garden's appearance after applying them, although your water savings can be significant. The techniques allow for garden choices while saving water and reducing your work.

Begin with planning
   Get your ideas on paper before you get your hands dirty. This technique is especially helpful if you plan to make installations over a period of time.
   Start with a base-map of where your house, paving, and utilities are situated on your lot. Then, divide the remaining landscape into water-use zones, where you'll place your favorite plants.
   Next, consider which features you can take advantage of. For example, an exposed area that always gets baked by the sun could become a low-water zone. Try to minimize the size of high-water zones and maximize the low-water zones, especially if you are dealing with a large landscape.

Appropriate lawns add to the effect
   Lawns are classified as high-water zones because people water them more to keep them green during our dry summer months. Consider how much lawn you need, and where to put it. Keep the lawn on a flat surface and size it to your needs.
   Separate your lawn from plantings that require less water, and you will automatically see an increase in your savings. You could put the mower away if you plant quick-growing, ground hugging plants, some of which tolerate a certain amount of foot-traffic.

Appropriate plantings
   You can create more no-water zones by planting Northwest native plants that fit your specific yard situations. Be sure you'll be able to water these plants until they become established. Even if you choose exotic plants, group them in your landscape according to their similar needs for water, sun, and soil. Take note of "micro-climates" created by the shadow of your house, fences or walls and other established plantings.
   Be sure to consider your garden's growth in five or more years from installation, and choose plants that fit your ability to maintain them properly. If this seems daunting, your nursery professional can provide good planting choices.

The benefits of good soil
   Before you install your plantings, consider soil preparation, which can increase just about any landscape's water efficiency. Next to over-watering, poor soils are the most overlooked factor involved in unhealthy plant growth.
   Lawns and plantings that are healthy won't attract disease and insects as readily as plantings under stress due to poor soil preparation. Build your soil to hold the right amount of both water and air for healthy lawn and plant growth. Incorporating well-composted organic matter to a depth of six inches may be all that you need.
   Some Puget Sound soils are composed of glacial cobble, clay, or bedrock. In these cases, add amendments to a depth that accommodates the rooting of your lawn or deeper rooted plantings. Choose plants adapted to your present soil condition and site them properly.

Irrigation vs. irritation
   Before you put those plants in the ground, determine how you are going to water them. An inch of water a week is all most plants need. If you have a rain gauge, you can track the amount.
   Some areas of your garden may never need to be watered. Or, poke a hole in your soil three to four inches deep to reveal what's happening below the surface.
   Repeat water applications for short periods of time where soils are compacted, sloped, or composed of quickly draining sand. Apply water early in the morning so the sun doesn't evaporate it and when the wind isn't blowing.
   If you choose automatic irrigation, you may want the assistance of a certified professional to design, and possibly to install, an efficient system. The irrigation industry is developing water-efficient products almost as fast as the computer industry is developing ways to process the information.
   While a well-designed system may be a convenience, it can save water only if it is regularly maintained. An irrigation system that is zoned in coordination with your planting plan, that is correctly installed, and which is properly maintained can reduce a landscape's water use by up to 40 percent.
   Two must-have items for any irrigation system are soil moisture sensors and a rain shutoff device; both of which interrupt the irrigation clock when water isn't needed.

Mulching about in your landscape
   Now you can get out there with your plants and shovel. Top off with a good mulch, which has the desirable effect of out-competing weeds for water, nutrients, and sunlight, while enhancing the beauty of your landscape.
   As mulches break down, they also add nutrients, beneficial organisms, and texture to your soil. Try compost, wood, or bark chips, but don't apply deeper than two inches. Weed control may also come from plants such as quickly spreading ground covers and perennials.
   If you are watering, fertilizing, and mowing according to your lawn's needs, you can leave the clippings on the lawn to serve as alternate mulch. Thatch is beneficial if it is no deeper than 1/2 inch. If your lawn has a thatch problem, aerating, rather than de-thatching, improves this problem.

"No maintenance, please"
   Unless you want green concrete, there's no such thing as a no-maintenance landscape. A few simple techniques can influence your water use.
   Take lawn mowing, for example. If you can't remember the last time the blade of your mower was sharpened, you're probably losing water through ragged grass leaves.
   If you have an automated irrigation system, it's important to reset the clock at least monthly to accommodate for seasonal variations.
   Look for water-wise demonstrations at the Woodinville Water District, 483-9104.