"Tyra Trevellyn" wrote in message
...





The tricky thing with rosemary indoors in wintertime is to make sure it
doesn't
get too dry or hot. The dry air and the sunny window can contribute to
powdery
mildew, which sounds like what you're seeing. Make very sure that the
(well-drained) potting soil absolutely never ever dries out completely and
that
there isn't an extreme heat build up that remains around the plants
overnight.
The powdery mildew won't necessarily cause the death of the plants but
the
environmental factors that cause it may do just that. I occasionally see
a
touch of PM on my overwintering pots of rosemary, but I keep them going
strongly anyway.

I haven't tried it but some recommend a dilute spray of baking soda
(one-half
teaspoon to one gallon water) to be used at the first sign of powdery
mildew.


Best,
Tyra
nNJ usa z7ish

rosemary is adapted to cool wet (well drained) winters.
sf bay, z 15