Lat year I had terrible problems with downy mildew on my onion bed.It
was a fairly wet summer (Herefordshire)and I tried to spray the onions
with a copper solution in late June when I observed the mildew,but
found that it didnt work.I think that one of the problems was that I
sprayed too late-some of the older gardening books suggest May or when
the onions are 8" or so high,so I will be trying that this
year.Another problem was that the spray (however fine the nozzle was
set) did not stick onto the smooth onion,but gathered in circular
globules.
So I am looking for a wetting agent. Some have suggested using washing
up liquid,but I do not know in what concentration and someone else has
advised me not to use it anyway.I went to our local garden centre,and
they told me that it is not available in the retail trade,since one
has to have a licence to use it.
So how do other gardeners get their sprays to stick to prevent their
onions getting downy mildew?
Michael