Creating Your Low-Water Garden

By Mika Ono

This is the time of year that Southern Californians can feel particularly smug when they look at weather reports predicting snow and freezing weather in other parts of the country. To make matters better (or worse, as the case may be), it's planting time for gardeners in Southern California.

Gardening in this region is not without its challenges, though, and author and gardening expert Nan Sterman spoke at a recent Lunch & Learn seminar series for Scripps California employees on how to create gardens that wisely use one of the region's scarce resources—water.

"We need to think about water differently," she said. "Water is like money. It comes and it goes. We should aim to garden within our watering means."

With its "Mediterranean climate" of long, hot dry summers and sporadic rain for a few months in the winter, the San Diego region imports 80 percent of its water, according to Sterman, and 20 percent of the state's energy is used for moving and refining water. Since plumbing innovations such as low-flow toilets and shower heads, most water is now used outside for landscaping.

Bye Bye Grass

Sterman identified lawns as one of the worst environmental offenders.

"Grass is one of the most resource-intensive plants we have," she said, asking whether anyone could think of another other plant that gets watered, pruned (mowed), or fertilized as much. "Think about getting rid of your grass. If you need some grass, see how much you really need and get rid of the rest."

While grass can be attractive, Sterman was full of suggestions of other gorgeous plants requiring less water. These included many varieties of trees, which give a garden structure; shrubs, which can bloom for months on end; perennials, which come in a variety of scintillating colors; succulents, the ultimate water conservers; ground covers, some of which can be walked on like grass; and bulbs, many of which require only moderate amounts of water.

Native California plants and others from similar climates in the Mediterranean, South Africa, and parts of South America are particularly well adapted to the local area. Many of these plants have features that help them thrive in hot, dry conditions, such as small leaves that don't give off too much moisture, leaves that point upward to escape the sun's direct rays, or fuzzy leaves that help the plant retain water.

Expert Tips

To conclude the seminar, which was hosted by the Scripps Research Counseling and Psychological Services Department, Sterman offered the following tips for the best results in implementing a low-water garden:

• Plant in the fall through the spring. In the summer, many plants don't adapt well to being transplanted due to the stress from the hot, dry air. Don't worry if you transplant in the winter and don't see anything happening with the plants at first—you'll see results when the weather gets warmer.
• Pay attention to drainage. Most of the plants Sterman recommends prefer growing in soil with good drainage. You can test drainage by digging a hole and pouring a bucket of water in it, waiting until that drains, then pouring another bucket of water in. If the second bucket-load doesn't drain for a couple days, you may need to bring in soil with good drainage, and plant in mounds of it.
• Do your homework. Know the water needs of your plants, so you can group them together in "hydrozones" and water these areas accordingly.
• Match the mature plant size to the space available. You'll save yourself a lot of grief if you know how big the plant is supposed to grow before you choose where to put it in your garden.
• Start with small plants. Younger, less mature plants adapt best to being transplanted and often ultimately outgrow plants transplanted when they are larger and more mature.
• Water even drought-tolerant plants for one to two years after they are introduced into your garden to give them a chance to become established. After that time, you can cut back on the watering. Sterman notes that many plants need little watering in the winter; you don't need to water if the soil feels damp.
• Mulch. "If there's one silver bullet, it's mulching," said Sterman. "It improves drainage and encourages beneficial microbes." Make sure you don't put the mulch right up to your plants, though, as you want to leave a space around them to keep the trunks or stems dry.

Sterman's books include California Gardener's Guide, Volume II (Cool Springs Press, 2007) and, new in February, Water-Wise Plants for the Southwest (Cool Springs Press, 2010). Sterman is available to answer low-water gardening questions by phone on Tuesday mornings (8:30 AM to noon, Pacific time) and Thursday afternoons (1 to 4:30 PM, Pacific time) as part of the Water Smart Pipeline hotline, sponsored by the Water Conservation Garden, at (866) 962-7021. More information is also available at http://www.plantsoup.com/.

Send comments to: mikaono[at]scripps.edu

"We should aim to garden within our watering means," says author and gardening expert Nan Sterman.