Understanding How Plants Deal With Drought

Plants have evolved many strategies to grow in harsh arid climates. There are two main strategies employed by plants to cope with drought.

Drought Avoidance

Some plants simply avoid drought by growing only when there is moisture & then die or go dormant during drought. Many annuals live a short life (less than one growing season/year) existing as seed in the soil until rains come. Sometimes seeds can lie for many decades before sprouting. Some plants go dormant and stop growing during drought. These plants lose their foliage in dry weather; some even sacrifice branch limbs to conserve water. Specialized root structures store water & nutrients during dry periods (bulbs).

Drought Resistance

In this strategy plants live with drought. They resist drought by employing fascinating anatomical & physiological methods of moisture conservation. Special cells store water in the tissues of the leaf or stem (an example is succulents). Plants have developed protective coverings of hairs, & scales in order to insulate them against drying wind & sunlight. Some plants go deciduous in drought, continuing to grow & photosynthesize through their stems. “Carrot like” tap roots can reach into groundwater, while shallow “Net Like” roots absorb any significant rainfall. Some plants have decreased their surface area & lost their leaves permanently to reduce water loss (Example cacti).

Proper Irrigation Techniques

In arid climates irrigation is extremely important. Several techniques have been developed to irrigate landscapes more efficiently. Water only in the morning or in the evening, this decreases evaporation. The soil can only absorb so much water so make sure that water from sprinklers does not flow off the surface. The deeper the water penetrates the earth the longer you can go between irrigations.

Water Efficient Landscaping

Flooding or slow deep irrigations work the best, bubblers & micro sprays work best. Use mulches to keep the soil cool & moist. Do rely on a timer to water your plants, rely on the weather & how the plants look.

Pay close attention to the texture & drainage patterns of your soil: Dense clay soil drains poorly & can hold onto water. In these soils water less often but for a longer period of time. Sandy well drained soils require more frequent irrigations but for a shorter period of time.

Plant Selection

In order to be a successful landscaper & gardener, one must choose plants that comes from a similar climate as ours. Plants that succeed in our area are tolerant of heat, wind, & cold.