Summer Heat and Organic Gardening

garden shade for summer heatIt was nice while it lasted. The spring, I mean. If I had been one step ahead, I would have had everything planted sooner. Who could have known that it was actually May in March? I mean… really.

I really didn’t want to tell you all the drivel you can find on a zillion other websites about how to “Beat the Heat” of summer in your organic garden. We all know, mulch is our friend. Period. Water deeply and less often. “Easy.” Water in the morning. “We know.” I hear you all chime.

If it is wilted, water?

There are two schools of thought.

During high heat watering must be thorough and deep. If you can’t water sufficiently during hot, dry weather you are actually better off doing nothing at all and I mean nothing. Plants under severe summer stress regulate by becoming inactive. Pruning, fertilizing, spraying or otherwise encouraging growth can do more harm than good if water is inadequate. And good point number two for watering deeply is you create more drought resistance in the first place when you encourage plant roots to go deep in search of water.

If you are bold and brave a walk out to the garden at the end of a hot day and find your squash plants… well not only squash, I mention squash because of the large leaf size, but you may find other plants with many small leaves, like green beans ‘wilty’ looking too. Don’t  be too quick to think they need water. It may be that there is sufficient moisture in the soil but your plant’s roots just can’t keep up with the needs of the leaves. If the soil is already moist you are better off letting the plants catch up on their own overnight. The best time to check your plants is in the morning before it gets really hot and late in the evening when it starts to cool.

Some plants actually droop “on purpose” in order to prevent too much exposure to the underside of the leaf. The underside of the leaf is where “respiration” takes place. This is where the plant loses moisture. This is why checking out your plants during cooler periods of the day is far more telling. If they perk up on their own when the temperature goes down, then chances are there is enough soil moisture. On the other hand, if your plant is still wilted first thing in the morning, that would mean it is in need of a good soaking.

But from Linda Chalker-Scott from Washington State says…

Under normal conditions, plants only grow as many leaves as their roots can supply with adequate moisture. Plants whose evaporative losses routinely exceed their root uptake in a well-watered soil are probably

(1) planted in too hot a location,
(2) planted too close to other plants and losing in that competition,
(3) planted improperly, or
(4) have poor root establishment.

While some gardeners are adept at estimating soil moisture by hand, an inexpensive soil moisture probe might be useful for others (but is not always accurate).

Linda also says…

The danger of assuming that the soil is already moist enough is that it might not be in places where the fine roots actually are.

I was looking for something a wee bit less technical to share, what folks are doing to keep a bit of shade over their “full sun” garden areas. My friend Theresa shared her photos and ideas with me. She wrote…

I purchased 6′ beach umbrellas at Harbor Freight on sale for $6.99 and placed them in my square foot gardens of tomatoes and cucumbers.

They come apart in the center. During storms, I remove the tops leaving the lower pole stake in the ground, fold down the umbrellas and store in the shed.
During the heat, the umbrellas can be tilted manually to move with the morning, day, and evening sun positions.

A white sheet on the fence also protects the cucumbers from the west sun heat. They are loving it and are producing, slowly, but producing!

Garden Shade

Theresa’s garden umbrellas

There is a common consensus, a heat wave can dry surface soil quickly which dehydrates shallow roots, and water is also lost through leaves in hot weather, so your plants will need a thorough watering. Morning is the best time for it.

Eartheasy said it best…

Unfortunately, the long-term outlook indicates that in upcoming years we gardeners will need to hone our hot weather gardening skills. The measures described above will likely be common knowledge in the years to come.

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