Wilt caused by more than heat

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I can hardly wait for this year’s first harvest of summer squash. Last year was a bust because of the heat, so I have high hopes for a bumper squash crop this year. Mostly gardeners complain about losing their plants to the squash vine borer, but I have managed mostly to offset that pest pressure by delaying planting in order to miss peak egg-laying time. I have also used row covers, lifting them in the morning so bees can do their pollinating, then covering them during the day when mama wasp of the vine borer does her work. Ultimately, I think my best defense is choosing Romanesco types of zucchini, like Costata and Gadzukes, which prove more resistant than your average yellow or green types.
Tiny eggs
The tell-tale sign that the squash vine borer has struck is evident in the stem of the plant. First keep your eye out for the tiny eggs that are laid on the stem, the eggs may appear to be specks of soil, so look closely. They are tiny, flat, and shiny-mahogany in color and you should destroy them. Once the larvae mature, they will feed on the stem and cut off all nutrients to the plant. If you allow the eggs to hatch, the larvae will make their way to the base of the plant where they will poke tiny holes in the stem. Their work will leave a trail of “sawdust” and yellow excrement. Once the yellow material is evident, they have already entered the stem where they mature to their borer stage. You can split the stem open with a sharp knife in order to remove the borer, but you must be careful to cover the injured part of the stem with soil; water well and hope that it will recover. Don’t bother if there is a major infestation. There is nothing you can do to revive a dying plant.
How to not rot
If you have a history of squash vine borers, it is a good idea to turn the soil of your garden (if it is not frozen) several times throughout the winter to expose any over wintering larvae in the soil. Then follow up with either late planting, row covers or planting a resistant variety.
Just like tomatoes, squash also suffer from blossom end rot. Blossom end rot is caused by extremes of wet and dry that results in a calcium deficiency in the soil, thus affecting the developing fruit. Your best defense is to irrigate deeply and on a regular basis to avoid fluctuations in soil moisture. If blossom end rot does occur, you will notice a soft, wet spot on the blossom end of the fruit. To restore the calcium level you can apply a solution of 4 teaspoons of 96 percent calcium chloride powder per gallon of water to the plant.
Blame bugs
Another pest of squash is the squash bug, and I have found that they are super easy to control organically. Just lay a board on the ground next to your plants and in the morning go out to the garden and walk on the board.  The bugs that took refuge overnight beneath the board will be crushed!
If your cucumbers suddenly wilt, you can blame the cucumber beetle, both spotted and striped. This little yellow and black beetle is a chewing insect that spreads the wilt disease. It is especially troublesome because it spreads mosaic viruses and bacterial wilt, both of which have no remedy.
Bacterial wilt on cucumbers is marked by the wilting of several leaves on a plant, followed by the plants eventual death. During the process of dying, the fruit stops maturing and shrivels up. Cucumber beetles carry the bacteria in their mouths and infect the plant as they feed. A sure way to confirm bacterial wilt is to cut open the stem of a wilted leaf, squeeze the sap out, and if you see a white substance, touch your knife to it and see if it oozes out in a fine thread as you draw the knife away—this is the bacteria. The beetles need to be controlled to avoid bacterial wilt since there is no other treatment. Smash the beetles when you see them or use pyrethrin to control them.  
(Jeneen Wiche is an avid gardener from Shelbyville. She can be reached at Jwiche@shelbybb.net.)