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KitchenGardener
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Wilting Leaves On Squash Plants

So here is my philosophical question of the day, lol:

Even if its physiologically part of the plant's function, how can leave wilting not be hard on the plant?

As most of us do, I grow a variety of squash. I've noticed that on a regular basis, the same select plants wilt their leaves on unusually hot, sunny days. I know the plants do not need water, as I've just recently watered them. They always bounce back at the end of the day. The squash that do it the most are my butternut squash and my cucumbers; it never happens to my zucchini plant.

I admit I hate watching them do it. I feel for them. My visceral reaction is to want to grab the hose, lol! So while it doesn't happen often (I live in an area impacted by coastal breezes), what if it did? How much of that hot day wilting can a squash plant put up with before it is just too damaging to the leaves which are not getting the water fast enough from the roots? I know if I wilted like that day after day it would definitely take a toll on me...

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applestar
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Sometimes, wilting is just the plants' way of reducing surface area exposed to the sun, and while we may think they are suffering, they are just folding up the umbrella so to speak.

bri80
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Well, there's a lot of potential factors to consider. Personally I think temporary wilting is stressful on the plant. And by wilting I mean serious wilting, not a minor late afternoon droop on the bottom couple of leaves. The garden author I really respect and has never led me astray says that vegetables will reach temporary wilting point when the soil drops below 70% field capacity of moisture. So one factor may be how much moisture your soil is able to absorb when you water it.

Another factor is the root system. Squash have a very shallow root system that extends laterally. So surface moisture is important. If the top few inches aren't absorbing much moisture and it's going to the subsoil, then squash can have a hard time using it.

Another factor is leaf canopy. The greater the leaf canopy, the more moisture is being lost and sucked out of the ground via transpiration.

I think you should strive to not have your plants temporarily wilt, personally. Investigate your soil moisture situation. There aremeters you stick in the soil that will read out the moisture levels at different depths. I find this very helpful. Often a bed I think is well watered, isn't, or a bed I think isn't well watered is actually at 100% capacity at 8" deep. In the latter case I'll usually allow a little more drooping because I think it encourages the plant to seek water deeper and thus create a stronger root system.

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KitchenGardener
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Thanks. My soil is adequately moist, as I'm aware their roots are shallow. :wink: I believe its more a matter of these two varietals. Anyway, interesting to see that others don't agree either! I do what I can - and if this heat wave continues, maybe I'll shelter these several plants for the hottest portion of the day. I don't like to see my friends suffering!

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KitchenGardener
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applestar wrote:Sometimes, wilting is just the plants' way of reducing surface area exposed to the sun, and while we may think they are suffering, they are just folding up the umbrella so to speak.
Love this analogy! Will think of it this way from now on. :wink:

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KitchenGardener
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So I realize that of the various squash I have, the only one that consistently does this is my Waltham butternut. Anyone else have experiences with this variety?

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applestar
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Is it blooming or fruiting -- different stage of growth compared to others? ANYTHING different?

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KitchenGardener
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applestar wrote:Is it blooming or fruiting -- different stage of growth compared to others? ANYTHING different?
Hmm, good question. Younger plants than most of the rest, except two other pumpkin plants which are handling things with aplomb. :)

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jal_ut
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Here is an interesting read on squash roots:

https://soilandhealth.org/wp-content/upl ... 7ch32.html

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KitchenGardener
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jal_ut wrote:Here is an interesting read on squash roots:

https://soilandhealth.org/wp-content/upl ... 7ch32.html
Wow, thanks I had no idea their roots went so deep! I thought they were surface roots only.

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KitchenGardener
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I wanted to provide an update to the wilted leaves story. A few things I've learned since I posted this. As you recall, one of the butternut squash plants was wilting (or folding its leaves) more than the other. The one folding its leaves was close to tomato plants. As Applestar so aptly put it: Tomatoes are bullies. So I'm thinking the tomato roots were not playing nicely.

Now, several weeks later, all is well. 8) The squash plants have grown bigger and I guess have what it takes systemically so as not to need to fold leaves. Occasionally, on the really hot day, especially if I've forgotten to water in a while (ahem, who me?! :eek: ) all my squash might look a bit droopy (as everything does), but they bounce back. So all is well. No fruit yet on the butternut squash, but I do have sugar pie and winter luxury pumpkins well on their way...



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