Help! What is eating my brand new summer squash and zucchini?

I'm pretty new to gardening and am having trouble finding a straight answer to this question.
We just put in some new summer squash and zucchini plants that are a few inches high (we bought them already started from a garden shop). Today I went out to look at them and at first it looked like something stepped on them since they were laying on the ground. On closer inspection it looks like something very small cut through them at the base and left the rest of the plant laying there. This must have just happened because the plants are still green. Some of the plants are still attached but the stems look VERY thin.
Our plants didn't make it last year either but we thought it was because it got really hot and they dried out. I know this isn't the case this year since it has rained the last few days and like I said the plants are still green. But now looking back I suspect the same thing happened last year to our brand new plants. The year before we lived next door and couldn't keep up with the amount of summer squash the plants were producing.
Today I dug around the base and found a grub type thing near some of the plants but am not sure if this is what did the job. I have read about the kind that bore into the plant but these plants are so young nothing could fit inside. Is it the same thing just attacking from the outside? If so from what I've read elsewhere it seems like there is nothing I can do this year...is this true? and will they attack my other plants too? (peppers, tomatoes, leeks. broccoli)
Any help would be greatly appreciated! I don't want to buy more plants just to have them all killed off again.

There are pests that will bore into the stem of squashes, and yes it will kill the plants. Once they are established there they will keep coming back...this is one of several reasons to rotate crops; keeps the bugs guessing where to find thier preferred foods.

I am rather fond of using sevin dust on my veggies when I know there is a bug problem. It will not work on snails or slugs, but does work well for most other pests. I got it at walmart and it was cheap.
If I recall, the pest that attacks your squash will not be interested in your tomatoes or peppers or leeks. They will eat most any squash variety tho.
Have you tried to identify the pest? Also try asking the garden dept you bought your plants from..they will often have helpful advice specific to your area.
I put my squash on a trellis, which helped keep it away from the bugs on the ground, but then I watered after work/school and it got dark and cool, so my plants got fungus on the leaves. My squash fell off unripened and there was no produce.
I am again trying to grow squash this year, and so far so good. Only watering during the daytime hours and no fungus so far.

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Originally Posted by ambraenoopsy

I'm pretty new to gardening and am having trouble finding a straight answer to this question.
We just put in some new summer squash and zucchini plants that are a few inches high (we bought them already started from a garden shop). Today I went out to look at them and at first it looked like something stepped on them since they were laying on the ground. On closer inspection it looks like something very small cut through them at the base and left the rest of the plant laying there. This must have just happened because the plants are still green. Some of the plants are still attached but the stems look VERY thin.
Our plants didn't make it last year either but we thought it was because it got really hot and they dried out. I know this isn't the case this year since it has rained the last few days and like I said the plants are still green. But now looking back I suspect the same thing happened last year to our brand new plants. The year before we lived next door and couldn't keep up with the amount of summer squash the plants were producing.
Today I dug around the base and found a grub type thing near some of the plants but am not sure if this is what did the job. I have read about the kind that bore into the plant but these plants are so young nothing could fit inside. Is it the same thing just attacking from the outside? If so from what I've read elsewhere it seems like there is nothing I can do this year...is this true? and will they attack my other plants too? (peppers, tomatoes, leeks. broccoli)
Any help would be greatly appreciated! I don't want to buy more plants just to have them all killed off again.

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Here is what I found on an internet search for you:
The eggs of this vine borer are deposited on the underside of the leaves toward the base of the plant. Once they hatch into larvae, these larvae will bore into the stalks of the plant at the base. When there, they tunnel through the stem and eat it. Once they are mature, you will find them exiting the plants and burrowing into the soil where they overwinter until mature in the spring.


"This is what happened last year, and they waited until you planted again to attack this years plants too. Probably can't save these plants, but you can treat the soil, then try again with new plants and be very vigilant about looking for the eggs under the leaves. Scrape them off and dust or spray your plants when it is cool out."

It is unfortunate that this vicious cycle begins because you could have a healthy looking zucchini plant suddenly die and not know what caused it if you aren’t aware of the existence of this pesky moth. There are ways to control the attack if you catch it early enough, when you find zucchini leaves wilting or yellow leaves on zucchini instead of your zucchini dying.

You can use insecticides when the vines are young. Do it right as they start to run. Some of the chemicals used are pyrethrum, malathion or Sevin. You can apply these as dusts. You can even buy sprays. Both will work. You should apply these things every 7 to 10 days to keep the borers at bay. Do this for about five weeks and your zucchini should be free of vine borers for the duration, preventing zucchini suddenly dying.

For those plants already affected, you can keep the damaged bored area on the stalk covered with soil and make sure to water the plant regularly. You might be able to save them and change yellow leaves on zucchini back to green in no time.

Definitely sounds like squash vine borer to me.

http://www.gardeningblog.net/2008/08...sh-vine-borer/