Jim Thomas writes:
You should do what I found out on this (or another) newsgroup several years
ago:

When you get both male flowers (regular stems) and female flowers (stems that
look like little zucchini), take a small paintbrush, use it to get pollen
from a male flower (inside it, at the stamen) , and brush it on a female
flower (inside it, on whatever it's called). You'll get the idea. It will
increase your squash yield by a bunch.

You are right, but only up to a point. For pumpkins, squash, etc., it
is true. But most home gardeners harvest their zucchini while they are
small--at most a day after the flower opens. At this stage, it is
immaterial whether the flower has been pollinated or not--the fruit is
of a size perfect for picking. Only if you intend leaving the fruit to
reach a more mature marrow size need you bother about the pollination.
This is the beauty of zucchini--you don't need bees (or paintbrushes)
to get your crop. Picked at this stage (on the day that the flower opens)
the fruit is at its tastiest and most tender, and the plant will go on
to produce tons more fruit if you keep picking them early. If the flower
is not properly pollinated the individual fruit must be harvested while
tiny, it will never grow into a mature marrow; left on the bush each
fruit will wither and drop off within days of its flower opening.
--
John Savage (news reply email invalid; keep news replies in newsgroup)