What are some good summer watering practices for the landscape?

One of the first signs of drought stress in ornamentals and turf is wilting. Many of our favorite plants show drought related symptoms differently. The leaves of some plants may exhibit marginal leaf burn or leaf scorching while others will simply wilt.

We’ve already experienced dry periods in much of North Carolina in April and May. Daily wilting of many spring-planted ornamentals has already occurred. These plants will be wilted by mid-afternoon on a hot day, but will be completely recovered the next morning after a soaking with the garden hose. An extended period without extra moisture and this temporary wilting can become a permanent, non-reversible situation.

This is known as permanent wilting point, and the next step is to remove a dead plant. Leaves wither and remain on the plant or drop completely; twig and stem dieback will follow.

There are several plants that are typically grown in many landscapes we can use as indicator plants. These plants wilt readily and are usually the first ones to show drought stress. They are azaleas, dogwoods, hydrangeas, most annuals and turf.

When these plants begin to look thirsty, you should have a plan to get water to the roots. A hand-held hose is probably the fastest plan of action, but we all know a lot of water is wasted when it is applied this way. Many home gardeners are not patient enough to apply enough water to each plant in order to relieve drought stress. Turn the water on very low and when runoff begins, go to the next plant. When you’ve finished watering all the individual plants, go back and repeat the process. The additional water will soak in much better this time.

The same strategy is true for sprinklers. Turn water on and when runoff occurs, move it to another location. Repeat the watering to really saturate the soil.

Remember to build an earthen saucer around individual trees and shrubs to act as a dam for hose-applied water. This will reduce the amount of runoff, and also be a much faster way to hand irrigate. Be sure to have a 3- to 4-inch layer of organic mulch around trees and in the flowerbeds. This will conserve moisture and discourage weeds. Once the plant is established, it is best to level out the earthen dam to prevent fill from settling around the base of the plant causing it to be somewhat buried.

If you are growing summer color plants in containers, it will be to your advantage, and the plants, to keep a water saucer under the pot. Pots will not dry out as quickly.

Pruning

Last week, I wrote about pruning to improve the appearance of plants in your landscape. Some have asked why not shear the plants?

There are several points to consider when shearing the plants with hedge clippers or electric shears and even in some instances–chainsaws. (Chainsaws are too dangerous to do fine pruning.)

When individual branches and stems are cut back to inside the plant, this will reduce the overall size of the plant and also reshape it. Natural, free-flowing forms of pruning cuts result from this type of cut that reduces labor and maintenance chores for the gardener. It also does not allow the harboring of insects and diseases as readily.

The real issue is what is your goal? If you like the formal look and have the time to perform this more labor intensive approach to pruning, then be sure to inspect the plants periodically to monitor disease and insect pests before they become a problem.