"Gyve Turquoise" writes:

Last year I grew a lot of sweetcorn plants together which I had
started at different times in modules. What I found was that for
some reason the plants all tried to produce kernels at the same
time. Presumably the pollen or something sets them all off. So the
less developed sweetcorn didn't have a good chance to make kernels
and in the worst case there were some very useless cobs with only
one or two seeds on them.

I don't think an early dusting of pollen would have any effect until
the silks are ready for it. It sounds like what happened is that
since you had different varieties mixed together, some plants weren't
able to get pollen when their ears developed to that point. In other
words, a stalk of variety A didn't get any pollen when it wanted it,
because it was surrounded by stalks of varieties B, C, and D which
kept the pollen from other A stalks from getting that far.

This year I'm going to grow different varieties for different
ripening times again. My question is how far do I need to separate
the corn plantings of different things to get them not to interfere
with each other's development like this. Any suggestions?

The last sweet corn I planted said either 250 feet or yards; I forget
which. Not many gardeners have that much space, so you just have to
do what you can. If you have two varieties that are likely to
pollinate at the same time, plant them at opposite ends of your garden
and hope it's not real windy when they pollinate. If you have
varieties with very different pollination times, you can plant them
close together and not have to worry about cross-pollination.

Make sure to plant your corn in sections at least four rows wide.
That'll ensure good pollination even if the breeze happens to be
perpendicular to the row.


--
Aaron