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The drought and heat that we are experiencing this summer has not been seen for many years and can do a lot of damage to your trees, shrubs, and perennials if they are not managed properly. The yellowing and curled leaves, fruit drop and other symptoms are effects seen on plants right now, but there can be intermediate and long-term damage if watering is not done. Secondary damage may be increased by wild life and insects feeding on garden plants and fruits. Long term damage may be root damage, diminished winter hardiness, twig die back and eventual death. So here are a few things that can be done to lessen the damage done by drought.
Prioritize the watering of plants so the most susceptible are taken care of first.The first class of plants that should have high priority are your trees and shrubs. This is most important with any new plantings. New plantings would include any trees and shrubs that have been planted in the last two years. When watering these plants it is necessary to let the water trickle on the ground for a longer period of time. This will ensures water gets down to the roots that take up the water. If you water for a short period of time, the water will not reach the roots where it needs to go.
The next class of plants that should have medium to high priority is your perennials, fruits and nut trees, and newly planted grass or sod. These plants have most of their roots in the top 6 inches of soil and if the drought gets severe, damage or complete death will occur if watering is not done.
Lower priority plants in extreme drought would be established lawns, herb plants and annuals. The reason for annuals and herb plants is they require the most watering to keep alive and can be replaced inexpensively or can be replanted next year when adequate moisture is available.
Lawns are composed of bluegrass and fescues that are adapted to drought conditions. They will go dormant in seasons of drought and will recover when the rains and cool weather appear in the fall. If you lightly water your grass during times of drought, the roots of the plants will stay shallow. When you stop watering, the roots will dry up and the plants will be more susceptible to drying out and death than plants that have not been watered. If you do mow the lawn the height should be increase by at least an inch to help shade and shield the crowns from drying out. Keep foot and equipment traffic to a minimum as the crowns of the grass plants become brittle and can be easily damaged by walking on them. This is especially true when the grass is brown and brittle.
These plants tend to have shallow roots systems. Frequent watering is necessary to keep them alive. Mulching these plants to shade the soil and keep the weeding down is an excellent use of mulch. The mulch should be organic such as ground bark, cocoa bean hulls, ground corn cobs, shredded leaves or grass clippings make excellent mulch. The mulch will allow you to water less frequently and will decompose which builds up your soil. When mulching use a little extra fertilizer to help break down the mulch.
It is very important to keep your gardens, perennial beds and annual beds free of weeds. Weeds are the plants that are best adapted to an area and will tend to be more aggressive when water is limited. These plants will then grow well and take up most of the moisture. This will make it even harder for the plants you want to grow and succeed.
Preferred Method of application - It is important to apply enough water to thoroughly wet the root zone when water is applied. Larger plants such as trees may require a drip for a couple hours to properly water. To use this soaking application it would be best to invest in a soaking hose or drip irrigation for vegetables, annuals and small fruit. Water is applied at lower pressure so it just trickles out of the hose to allow the whole root zone to be well watered.
When to Water- Water should be applied when the soil is completely dried out. Wilting or scorching of leaves is a sure sign of the need for water. Early morning is the best time of the day to water so the the leaves dry out by mid morning. Watering in the evening will sometimes lead to more plant diseases as the water on the leaves will not dry out and spores of the diseases will have all night to germinate and infect your plants.
How much - A good rule of thumb is to apply one inch of water per week over the surface of the soil. This will vary depending on the type of soil. If you have a heavy clay soil, less water is need, but if you have a sandy soil the amount needed may be an inch twice a week instead of once a week.
When thinking about the need for water, don't forget the wildlife that also is experiencing these hot, dry conditions. Put out a bird bath for the fine feathered creatures and maybe even a pan of water in a protected area for other wildlife. They also can suffer from the lack of water.