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COLUMN: Dry, hot weather is tough on plants

After five months of cooler, wetter weather than I’ve ever seen before, we’re about to experience some record hot temperatures.

After five months of cooler, wetter weather than I’ve ever seen before, we’re about to experience some record hot temperatures.

It looks as though the weather will be great for swimming in pools and lakes and for barbecues, and as nice as this may be, dry hot weather can be tough on our plants.

Sudden heat and soaring temperatures create a demand for moisture that cannot always be met on short notice by the root systems of many plants.

The result is burnt blossoms, damaged foliage and hard, stunted growth.

Fortunately, there are ways of minimizing the problems caused by a sudden hot spell.

The most immediate relief for plants is a thorough, deep watering. It is best to do this early in the morning when the plants will make the greatest use of the water.

Watering in the evening wastes water because plants simply transpire valuable moisture away. The other huge issue is where to water.

Soaker hoses around the perimeter of all trees and shrubs is the most effective way to water.

A little water is worse than no water.

When you water, saturate the soil deeply where the roots are to keep them going downward instead of upward in an effort to capture what little moisture there is.

The next most important task is to mulch many of your trees and shrubs with suitable material.

You should be looking for something that is a good insulator, can eventually be worked into the soil and has an attractive appearance. Garden compost is fine if it is well broken down, but its appearance is not always the best, especially when it dries out. Manures are also fine, but remember that they are slightly on the alkaline side and can cause problems with your acid-loving plants like rhododendrons and camellias.

If you use manures, be sure they have been composted for at least six months. Grass clippings are quite suitable in the short run but once dried out, they tend to look rather shabby. My preferred choice is always fir or hemlock bark mulch. Bark is a wonderful insulator; it looks great and makes a fine soil amendment. A covering of three to four inches around all your plant material will prevent a great deal of stress, especially for shallow-rooted plants like rhododendrons.

Hedging cedars are very shallow rooted and will dry out quickly in a few days of intense heat, so use soaker hoses to alleviate this problem.

A thorough watering is the most important stress-relieving factor for all the plants under the eaves of your home. Heat reflected  off buildings can be a real challenge for plants, so please do not neglect both the sun and shade areas under the eaves.

Here, too, I find soaker hoses and drip systems are, by far, the most efficient and thorough method of watering.

Remember, for all your veggies, annuals, perennial beds and  containers, try to get in the habit of watering very thoroughly to make sure the roots and soil mass are moist down deep, not just on the surface.  Water less frequently, but really soak the soil when you do water.

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