At this point in a dry season, any precipitation will help. Until it arrives, we need to take more care with water in our gardens.

Reduce the impact that hot, dry weather has on your plants by planting flora adapted to the average moisture and soil type of your region. Natives are a good idea but not the only answer for beautiful, lush gardens.

Gardens can be designed and planted to withstand warmer, drier conditions. Even if your landscape is well established, gradual changes can make a difference. For example, a rain garden is probably the best step you can take to keep water where it falls. It’s an area that has been prepared so water percolates efficiently into the soil and around the plant roots. And the excess can soak into the soil and help recharge aquifers - the fresh water that flows underground in huge natural reservoirs. Take care, though, because some aquifers have been breached with pesticides and other chemicals in recent years.

Xeriscaping
When you choose plants, follow the principles of water-efficient landscape design. This is called ‘xeriscaping’ which means planting for dry conditions, and entails installing drought-resistant plants and delivering water to them efficiently. When you replace plants in an established garden, plant those that will withstand dry conditions in dry areas and wet conditions for moist sites.

Design for shade and coverage, as well. Evaporation from plant leaves has a cooling effect. Ideally, plant material, including trees, shrubs, perennials and annuals, should cover 75 to 80 percent of the soil.

Group plants with similar water requirements. Some perennials and grasses that can tolerate drought include coreopsis, autumn joy sedum, lavender, gaillardia, blue switchgrass, blue oat grass and Elijah blue fescue. Abelia, caryopteris, cotoneaster, viburnum, potentilla and spiraea are more drought-tolerant shrubs.

An established planting of black-eyed Susans, liatris and purple coneflowers is also drought tolerant and might not require watering every week, depending on their exposure. In contrast, moisture-loving cardinal flower, blue star amsonia, blue flag iris, acorus and other plants that prefer cool, protected sites could wilt and dry without irrigation. Instal plants in a growth medium that is at least one part compost to two parts existing soil. Earth that is rich in organic material will give flora its best shot at beating the heat and drought. Appropriate use of mulch can slow evaporation of water from plants’ root zones. Use organic mulches, such as compost or bark. Never mulch against woody plant trunks, and spread not more than two inches thick. But sometimes plants still have to be watered, especially during their first year or two as they get established.

Proper watering begins with common sense. First, make sure the supplemental water is needed. The best way to find out is to stick your finger in the soil and see if roots are moist. If you don’t want to get dirt under your nails, try a moisture meter, which is available at garden and home-improvement centres. Different areas of your garden will have different drainage patterns, so you might not need to water everywhere.

If you can’t feel moisture, irrigate - but do so efficiently. Don’t just sprinkle plants. Provide a soaking, enough to penetrate down and around the roots.

One do-it-yourself method is to punch four or five small holes into the bottom of one-gallon plastic beverage jugs and fill them with water. Set one to five around each plant, depending on its size. Most of the water will drip into the area where the plant can absorb the moisture.

Timing is also important. Water plants in the early morning or early evening, when temperatures are lower and winds are lighter, to minimise evaporation. A soaking hose is better than a sprinkler. A timed irrigation system is ideal for turf and can even save water.

Drip irrigation, in which a porous hose leaks water slowly into the soil, is preferable, but lawns need to be watered from above with sprinkler heads. Turf can go three weeks to a month without rain. Leave it a little taller when you mow. Longer blades shade root systems and hold soil moisture. Leave clippings to help hold moisture. And you can cut down on water consumption by reducing the amount of lawn.

Save water by collecting it from other sources and directing it to the garden. Some sources of second-hand household water are air conditioners and dehumidifiers. Gray water, such as bath, dish and cooking water, can also be used in the garden. Put it on the soil, not on the foliage. Don’t use water that contains bleach, detergent or fabric softener.

Weed regularly. Weeds use moisture that could be available to the plants you want.

Lerner is president of Environmental Design in Capitol View Park, Md, and author of  ‘Anyone Can Landscape’ (Ball 2001). Contact him through his website, www.gardenlerner.com.

LA Times - Washington Post