In article . com,
"rile" wrote:

Once again the dreaded zucchini has stumped me. I did an all out
effort to thwart the vine borer and might have succeeded. Now, other
problems are cropping up.
I think I'll have to hand pollinate the plants. One plant has all
kinds of blossoms and has had them for several weeks but no fruit.
That plant grew from seed from last year's harvest. Is it possible
that it will only produce male flowers? When I do hand pollinate, do I
have to do it from one plant to another or can I do it within one
plant?
Another plant that did produce one zucchini has another problem. It
keeps looking very wilted. We have had 5 or 6 days of about 90 degree
temps and at one time, it looked so bad I thougt the vine borer did get
it. After watering, it seemed to come out of it but looked bad the
next day. Also, some of the stalks seem to be dying off with the
leaves turning brown. I noticed that some of the dirt around the base
had eroded it away. Would this cause the wilting problem?

I wish you luck. I had my own period of hand wringing as my squash
season started to unfold but it ended-up being much to do about not much
of anything. I'm guessing, and I haven't been particularly good at it,
that pollination comes in fits and starts as the season begins and then
settles down into a predictable routine, I hope. For a week, I ran
fertility clinics for my "zuch" and my crook-neck but they seem to have
no further need of me in their private lives.

The wilting, the positive response to water, and disturbed dirt at the
base of the other zucchini makes me think that the roots have been
damaged, possibly by dogs or cats running amuck.

I have dogs and cats, and I try to protect some of my more exposed
plants from them by using strategically placed tomato trellises. You may
want to give the wilting "zuch" some B1 or bone meal to help it scab up.

We're also having hot weather high 90s, low 100s (not desert hot but hot
none the less, and a nice change from the cool summers of the last six
years) along the north coast of California but the tomatoes seem to be
loving it.

Good luck