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Plant Doctor Archive
Unhealthy roses

I
AM new to gardening. We recently bought our first home and have
inherited some old rose bushes. They appear to have black spot.
What should I be doing at this time of the year to tidy the plants
up and get them looking healthy again for spring? Can I prune them
now?
ROSES can be a real joy, but do
need some work. You shouldn’t get too much Black Spot in New
Plymouth, as it is not as humid as other regions. However, to
combat it you can use Yates Shield or Super Shield. Alternate with
other fungicides like Bravo. You can do a light prune now to get
the plants under control. Prune about one third off at once, or as
you pick flowers. Take out any dead or badly diseased wood, and
prune good shoots back to an outward pointing bud. Throughout the
winter use a winter spray programme of Yates Champion Copper and
Conqueror Oil until the spring growth shows. Some very old rose
bushes can be encouraged to put out growth if you scrape off some
of the old bark at the base with a wire brush.
Weekend Gardener, Issue 93, 2002, Page 20

