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Old 25-06-2003, 06:08 PM
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Default roses - black spot on leaves..white spots on roses?

"DigitalVinyl" wrote in message
My neighbor has two trellises of roses. One is in bad shape, most of
the blooms are rotted and the rest are dying. MANY of the leaves have
black spots. The more covered leaves are turning yellow. There are
dropped leaves.

Everything matched the description of Black Spot.

The one thing I noticed was there were white spots on the roses,
particularly the outermost petals. They look like bleach stains--the
edge of the spots quickly turns from the rose's pink into a pure
white. They are *very* covered with these white spots. Far more than
most of the leaves with black.

Are "white spots" another, less mentioned symptom of black spot?
Or is this something else?
DiGiTAL ViNYL (no email)
Zone 6b/7, Westchester Co, NY, 1 mile off L.I.Sound
1st Year Gardener

It's botrytis, a fungal infection freqeuntly precipitated by too much rain.
It can affect stems and leaves as well, but it's primary residence in in
buds. On white roses, it manifests itself by pink spots, and on dark roses,
the spots are sometimes whitish or brownish, depending on the rose.
Fungicides used to prevent black spot can be helpful in it's control, but
it's more difficult to prevent, so 100% control may not be achieved.
Frequency of preventative spraying is a key to the most successful control.

MS 7b