I have marrow plants which have lost both of the first flowers which were
part way thru' the 'collapse' which comes after the full flower.
The first occasion I found the collapsed flower lying on the ground
underneath the 'square cut' stalk on which it had been growing.
The second occurred as I watered the plants, with a can and spray rose, the
part collapsed flower fell off onto the ground leaving, again, a square cut
stalk!

The first occasion I blamed slugs or birds for severing the flower. The
second time was obviously the watering, but I didn't think the flowers were
so delicate. Could it be though some failing in the plant that left both
flowers vulnerable to the slightest knock?

Please help, thanks.

A 'first season' gardener!

Nigel