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Gardening Tips: It’s too hot, too hot... to garden

July 6, 2018 11:36 am Updated: July 6, 2018 11:53 am


I fear that I brought the hot, muggy weather back with me from Florida! Last week’s heat wave made it too hot to garden or fish for most of the daytime hours. It also put a great deal of stress on our garden plants and stressed plants are more susceptible to all sorts of problems. Closely mowed lawns have already begun to turn brown, as the grass goes dormant, while lawn weeds are far more tolerant and will multiply. Lawns kept mowed at 3 inches or longer remain green. Never apply fertilizer to dormant plants (especially lawns) since this practice only makes things worse. Do not apply any weed killers either, since some weed killers will volatize (turn to invisible gas) and may damage plants that are not even close to where the herbicides are sprayed. I have seen tomato plants damaged by herbicides more than 100 feet away from where the weed killer was used. Wait to mow the lawn until it cools off, even if the grass is getting really long.

Plants deal with excess heat by evaporating water out of tiny pores on the undersides of the leaves called stomates. Regardless of how well watered the plants may be, at some point they cannot evaporate enough water to keep cool and still continue to grow. They shut the pores down which causes photosynthesis to cease and may wilt severely as a result. Don’t overwater, even wilted plants, since this can cause soils, especially heavy clay soils to become soggy and allow pathogens to rot the roots. The best time to water your garden is in the early morning, which allows time for the water to evaporate before fungal spores can germinate.

Another way that some trees deal with heat stress is to drop some leaves that it really does not need. Trees produce more leaves then needed for photosynthesis and can spare them with no ill effects. I have observed this on my peach trees and birch trees as well. Remember that trees and shrubs planted this year need about one inch of rain or equivalent watering every single week, those planted last year need an inch every two weeks and those planted 2 years ago, still need about an inch every few weeks. Overhead sprinklers waste a great deal of water, whereas a hose placed at the base of the tree and allowed to just barely trickle for 15 minutes or so, works very well.

The anticipated flush of chanterelle mushrooms I wrote about last week did not really pan out as well as I had hoped, although I did pick about a quart this past week. The amazing, but mostly dead, sugar maple tree near my house, once again produced a flush of tasty oyster mushrooms that I almost did not see. Make sure you check all sides of any tree that is bearing mushrooms! I drove by this tree a couple of times before I decided to check it out carefully and was rewarded for my diligence.

Most pest insects, as well as spider mites, are not at all bothered by the heat wave and may even thrive under these conditions. Certain diseases, such as powdery mildew, also like this weather! Delay spraying anything however, until temperatures drop below 80 once more.

On a positive note, this appears to be a great year for Monarch butterflies which feed primarily on milkweed. Milkweed in full bloom produces a very sweet scent as well and milkweed blossoms placed in water will make it taste very sweet. Unopened, still green and small, milkweed buds taste very much like broccoli when boiled for five minutes or so. I don’t recall seeing as many as I have seen this year. The fireflies, aka lightning bugs, have been pretty amazing as well!

If any readers are looking for some flexible hours, part time work, doing some lawn mowing for a golf course, or shearing Christmas trees, at a tree farm, I know of two openings in Greene County. The owners are looking for mature people who enjoy the outdoors!

Reach Bob Beyfuss at