Answer: Hollyhocks are very susceptible to rust, a reddish brown leaf problem. Rust fungi are ever-present in the
environment, just waiting for warm, humid conditions to
favor their growth. The best deterrent is to grow your
plants with good air circulation to help
the leaf surfaces dry quickly and discourage the sprouting of
spores. This would mean avoiding overcrowding and avoiding evening watering as well as avoiding overhead watering. Take care to inspect and remove any leaves that have the silvery-gray or
orange growth on the undersides and carefully clean up and remove all plant debris from that area each fall. This should help reduce the carry over from year to year. If it looks like you'll be in
an on-going battle with this problem you might try Gardens Alive's
Soap Shield ( Gardens Alive, 5100 Schenley Rd., Lawrenceburg IN
47025; 812/537-8650) to prevent future outbreaks.
If you are not sure the problem was rust, you might want to take a sample to your County Extension (675-2595) for identification and suggestions on how to control it.
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