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The Spokesman-Review Newspaper
Spokane, Washington  Est. May 19, 1883

Gardening: Careful watering helps during grueling heat, Pat Munts says

Microsprayers are an inexpensive way to keep a garden watered in hot weather. They are plugged into a poly pipe attached to a hose bib. The head can throw an 8-foot circle of water. (Pat Munts / The Spokesman-Review)

How quickly we went from being drenched in record rains and cool weather to roasting in 90-degree temperatures. At last check, there wasn’t any relief in sight so we are just going to have to wait it out like we did last winter’s snow.

Hot days with low humidity and a moderate wind can desiccate plants faster than you can get water on them, so here are some tips to help them out.

Water lawns so the water gets deep into the root zone. It is better to water for an hour three times a week than for 20 minutes every day. Water between 4 p.m. and 10 a.m.to avoid the heat of the day. Watering at night here doesn’t lead to disease issues found in other parts of the country because our humidity is usually very low. Don’t fertilize until mid- to late September, because the grass has basically gone dormant until it cools down and can’t use it.

At this point in the summer even drought-tolerant trees can benefit from deep watering every couple of weeks. Snake a soaker hose around the drip line of a tree and leave it on overnight so the water can get a foot or more deep where the roots are.

If you have prized plants that are getting scorched by the sun, shade them with a large beach umbrella or some shade cloth. Garden centers like NW Seed and Pet offer it by the foot. The fine mesh allows air and water in but blocks 10 percent to 20 percent of the sun’s light.

Container and hanging baskets may need to be watered multiple times a day to keep up with the plants’ transpiration. If the water runs right through a pot or hanging planter, slowly apply a dribble of water over an hour or so to allow the soil to soak it up. Hanging containers can be taken down and placed in a large tub of water to allow the root ball to absorb water. Consider buying an inexpensive drip irrigation system and a battery timer to keep things watered.

Vegetable gardens are at their peak of production now so keep them evenly moist. If tomatoes and peppers dry out too much between waterings, the fruits can develop brown, soft patches called brown rot. Like lawns, it is better to water vegetable gardens for longer periods of time, three to four hours a week. Use sprinklers or soaker hoses on a timer to uniformly get water on the plants. Cover any bare soil with grass clippings or pine needles to reduce evaporation. Keep buzzing the tomato flowers with your toothbrush to help ensure the flowers get pollinated properly.

Powdery mildew on squash and other plants will start appearing as the nights start to cool. It appears as fuzzy, white patches on the leaves. A severe infection can stunt the plant. Begin applying a fungicide every one to two weeks now through the end of the summer to reduce its onset.

Pat Munts has gardened in the Spokane Valley for over 35 years. She is co-author of “Northwest Gardener’s Handbook” with Susan Mulvihill. She can be reached at pat@ inlandnwgardening.com.