Drought Tolerant Plants

No strict definition

First, it's important to remember that all plants need some water, at least occasionally. What plants you classify as drought tolerant will depend on what you call a "drought", and what you regard as "tolerant".

If you're used to rain every day, one dry week might be called a drought. In other locations, weeks or months without rain might be normal. In coastal Queensland, heavy rainfall episodes with plentiful supplemental water out of the tap were once considered "normal". Unfortunately, the current climatic and water infrastructure situation now makes it unfeasible to grow many types of plants that would be possible in decades past.

Meanwhile, "tolerance" may mean growing and flourishing under consistently dry conditions to some gardeners, while others may be satisfied with a plant surviving dry periods somehow until until better conditions arrive.

Furthermore, other environmental factors will affect performance for a given amount of watering. These might include exposure to wind, soil type, plant nutrition, intensity and duration of sun exposure, and other stress factors. Modification of the microclimate (shading, windbreaks, soil conditioners etc) may assist survival under a given irrigation regime.

For the purposes of this page, the focus will be on plants that can survive and look reasonably good through extended dry spells in tropical and subtropical regions with little or no supplemental watering. Such plants should tolerate high summer temperatures combined with humidity, high light intensity, and little or no frost in winter.

Establishment

When it Rains

Roses are very forgiving plants, tolerating harsh dry times as well as the rainy periods that will eventually return. Depending on soil type, once a week watering is usually preferable. In dry times roses can survive on minimal water, however, you can't expect the usual habit of flowering each 6-8 weeks.

Mulching is essential for water retention and insulating the ground. Water crystals can work wonders but with many different types on the market, select wisely.

Potted roses can be planted at any time of year. Prune lightly after each flowering and a major winter prune in late July to early August. Roses work very hard, so they need to be fed. Make sure your roses have at least 5 hrs of sun per day.

Attractive gardens are not the exclusive domain of ornamental plants. Herb plants intermingled with ornamentals can create a very unique and useful garden.

Perception of herbs as a group are often limited to those plants of herbaceous nature, that is, plants with no woody tissue. A broader description would be a plant that has medicinal, culinary or industrial uses. Many are attractive specimens in their own right.

Drought conditions do not adversely affect most herbs, rather it is the watering habits acquired from tending soft, ornamental plants that are too much for these resilient and hardy plants. Herb plants are usually killed by over-watering.

Below are a few suggestions for herbs to add to your garden. Selected plants are not only tolerant of dry conditions but also do well with regular rainfall.

If creating a native garden, using species that occur naturally in your area can be beneficial environmentally as well as provide an extra interest to the garden. One of the problems, however, is finding information on what grew locally originally.

Toowoomba gardener and author Patricia Gardner has come to the aid of Darling Downs residents with her Toowoomba Plants book duo, the first volume of which (Trees and Shrubs) is available now. It contains detailed descriptions of 277 trees, shrubs and mistletoes.

The book isn't just for native enthusiasts, however, because Patricia concentrates on species suitable for residential properties. The range of drought-tolerant suggestions will help homeowners in the Toowoomba region and beyond create attractive gardens with less water.

There is a particular focus on "dry rainforest" species. Patricia says these are good for homeowners wanting a rainforest look at home, because they are not only drought tolerant, but they tend to be smaller-growing than species from high-rainfall areas.

More Online Information

There's more about low-water use gardens (general design, gardening practices etc) here: Water saving gardens. The links on that page may contain additional information on drought tolerant plants.

Queensland

Regional pages Includes links to many City and Shire Councils in Qld, plus local environmental groups. These sites may have their own lists of plants suitable for local conditions

Plants suitable for low rainfall areas Department of Natural Resources and Mines, Queensland (PDF)

Drought Tolerant Enoggera Species Save Our Waterways Now

Gardening in Hughenden Society for Growing Australian Plants Queensland Region, Inc.

Australia

Garden Tips for the West Kimberley and Garden Tips for the East Pilbara Water Corporation, WA

Some Drought Tolerant Native Plants at the Australian National Botanic Gardens

Recommended Local or Australian Native Plants for Alice Springs Alice Springs Town Council

International

Note that some plants recommended in international lists may be weeds in Australia

How Plants Cope with the Desert Climate Arizona-Sonora Desert Museum

Drought Tolerant Plants for North and Central Florida University of Florida

Arizona Dept of Water Resources Low-Water Use and Drought-Tolerant Plants Arizona Office of Arid Lands Studies

Arid Plant List an illustrated guide to common landscape plants used in and around the Tucson area. University of Arizona

Include gray-leafed plants in '05 gardens Mississippi State University

There are also some links about lawns here: Lawn and Turf supplies. If you're interested on the effects of water and heat stress on plants, check Trees - general issues and Weather & Climate in Qld. Pages dealing with individual plants (Site Search) might have more information on particular species.