Nightowls
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What is happening to my squash plants?

At the end of May, I planted two Zucchini plants and started a bunch of seeds (pumpkins, watermelon, scallop and kuri squash).

In July (or maybe it was June?), I noticed that some of the Zucchini leaves were turning yellow and the stem was collapsing. It seemed to be the ones that were on the ground underneath other leaves and/or blocked from the sun - so I blamed that. A couple of weeks later, I noticed a bug on one of the leaves - it was a squash vine borer! I gave the plants a detailed look through after that - I even looked in some of the vines - but I could not find anymore borers. Then I was thinking it was a disease like bacterial wilt. However, doesn't that usually kill the plant quickly? Its been awhile, and my other squash were growing fine, so I thought 'maybe, they are just not getting enough water.' I bought a cheap little soil moisture meter and, sure enough, it says that most of the garden was near dry.

But... :( on Friday, I noticed some of my pumpkin leaves turning yellow.
Again, I was leaning towards not enough water. But on Saturday, it rained for several hours and on Sunday they were worst. Even my beautiful kuri squash plant (none of my squash has set fruit yet) was showing signs.

I think I saw a squash beetle - just one; couldn't find any eggs.

So, I don't know what to think, is it bugs, disease, improper care (water/nutrients), or a combination of it all?

Here are some pictures - ignore the white its just DE.

https://www.flickr.com/photos/moon_owl/sets/72157630841570230/detail/

:cry:

Bobberman
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Look for black or orange egga on the leaves. Also it seems to me that wood chips seem to cause squash and zucs to die off. Has anyone else noticed that? I think the chips are depleeting the the nitrogen for the squash!

Nightowls
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I looked on several leaves and didn't see any eggs but I'll give it a better look-through tonight.
...wood chips seem to cause squash and zucs to die off
I wish I had wood chips down then I would have a reason; I do not have any mulch down.

Are squash heavy nitrogen feeders? When my non-zucchini squash was smaller I was watering with Alaskin Fish oil (15-1-1) about every five days and they were fine. Now that they have buds, I have used Schultz liquid plant food (10-15-10) the last couple times.

Bobberman
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Too much fertilizer will deplete the water for them! Stick with the fish but very delute every two weeks. Fertilizer is like a sponge too much sucks up the water away from the plant roots!

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jal_ut
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I am leaning toward a combination of not enough sun, not enough water, and not enough soil nutrients.

A yellow leaf here and there and some with holes in them is nothing to worry about if the plant is vigorous and has what it needs. The vine borers are to worry about. They can ruin your plants in a hurry.

I see a tall fence on one side and a building on one side. How much sun does the plot get?

I will suggest some 16-8-8 fertilizer and put it on per the recommendations on the package. Then water deeply.

Your plants are in no way over fertilized. Leaves of squash often get to 12-16 inches across and will be 24-30 inches above the ground. Yes, all squash need loads of nutrients and especially nitrogen.

[img]https://donce.lofthouse.com/jamaica/gdn_july9_3.jpg[/img]

[img]https://donce.lofthouse.com/jamaica/gdn_july9_4.jpg[/img]

These got urea, 38% nitrogen three times. They get watered deeply once a week. They are in full sun all day. I might add, bright Utah high altitude sunshine.

Bobberman
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I use urea also but on my tomatoes it seems to make them go crazy with too much growth and too many suckers! Osmocote is also good but way too expensive and is simply coated urea for time release.!

Nightowls
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Location: Zone 7 (Long Island)

Jal_ut, it looks like you have some nice scenery - and veggies - there.
How much water do you give them? And what type of soil and temperature do you have? My natural soil appears to be a sandy/silt and I mixed some miracle gro garden soil and peat into it. Our temperatures have been in the 80s with several really humid days.

What is the difference in not enough water yellow and too much water yellow? I would think that not enough water would cause the leaves farther away to yellow. But its the ones closest to the main vines that are yellow and it's not a crumbly dry yellow. And I still haven't seen any eggs or more bugs.

Most of my land is part sun/shade but some things are still growing. I put some compost down the other day and I'll let just let that do the fertilizing for awhile; I do not want to add much more nitrogen - some of the plants have already grown over the 6ft fence and down the other side to visit the neighbor.

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applestar
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If you saw SVB moth, then the larvae migh already be inside the stems. Do you see any split stems and/or mushy sawdust clumps near the base of the stems or ALONG the stems, particularly just "south" of yellowing leaves?

Nightowls
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:D I looked again last night and finally saw some sawdust. Yes!!! :clap: :clap: :clap: :clap:

:P Not something I should really be excited about but at least I know what is wrong now and can take action.

I want to try injecting the vines with btk. Would this work :arrow:
https://www.acehardware.com/product/index.jsp?productId=3909469
with a diabetic syringe?



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