Summer squash usually looks a bit chlorotic to me, but yours looks a little more so, as well as a bit stunted. The ground seems plenty moist, so lack of water probably isn't the problem.

My squash frequently wilt during mid summer when the temps are well into the 90's, then firm back up when the sun gets low or a thunderstorm comes over. So, it could be your temps. causing the wilting if it is warm. Is the squash located on the south side of a house or wall which is fairly close? That could intensify the heat/light.

If your temps are currently milder, then your roots probably aren't supplying the moisture the plant needs. Could be root disease or something restricting root growth.

Based on the color and apparent size of the plant, I would be tempted to provide some nitrogen to the soil if you haven't recently and give it a weekly foliar spray of micronutrients, something which includes iron and zinc, for several weeks.

Your climate and soils are most likely very different from mine, so there could be something else going on.

Well to my fear I found the dreaded squash vine borer in my squash all is lost what can I do to keep these nasty guys at bay nexted year .I might plant more this year but not if there is no way to keep this away.I yanked up all my squash and killed all the nasty worms some were huge.

Too bad that you ripped out the plants. I cut the vines open and slice the grubs and then bury the cut part of the vine. Squash will reroot any where that they touch the dirt. You can also inject BT into the stem to kill the grubs.

I have buried a long stem of the vines in the past long before I see any damage just as a precautionary measure.

I also start new plants every month or so just in case the attacked plants do not recover.

CrAzY LaRrY

Here in south TX it is just soooooo hot in the mid afternoon that squash and other veggies too go into that wilt looking stage and then back later in the evening...they sometimes look almost dead..as long as you are watering properly they should be ok..at least mine always do that and I usually have a decent crop...before they die from wilt, they will succumb to the borer...

Your squash look like mine! Mine were beautiful until the temps started to hit 100. This is our first garden. We planted in late March and we have lot's of tomatoes (green ones) but the squash are looking bad - the ones that are growing are half yellow and shrivled up. I am very discouraged!

Txgarden7 I lost all my squash to the squash vine boribug and all my cucumbers I saw the nasty buggs in the main stem eating all the way to the roots.Check yours hope you dont have them.

Yep, it's normal in the heat; they wilt like that to conserve liquid and prevent further loss through transpiration in the hottest part of the day.

I water in the evenings and make sure they get a good solid DEEP watering twice a week or more.

So far my Buttercup is doing fine, but the Butternut and my very big Hubbard are wilting. Vines and leaves seem to actually die. Last year I just dug them up, tho I did get some squash. I have considered they were getting too much water, so am cutting back. Our soil is very alkaline so gave them another miracid shot today. Haven't looked for or seen the worms, but will check that our more closely. Still not sure what is going on. In raised brick with about 90 deg weather. Never had so much trouble raising squash. They have always been so easy.