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Plant Doctor Archive
Rust in Roses
I
AM a very new gardener and last year launched into roses in a big
way. I was rewarded with gorgeous big flowers. I sprayed every two
weeks and thought it was easy. This year, however, disaster! One
whole section of roses is covered in unsightly rust — it’s very
bad — the flowers are stunted and malformed and the leaves orange.
I had been spraying fortnightly since the first leaves appeared,
alternating between Super Shield, Gild or Saprol.
RUST can definitely make roses
unsightly and set them back, but don’t give up. Saprol and Gild
are similar in fungicide chemicals, with Gild having the advantage
of killing insect pests as well. Keep spraying, alternating
between Super Shield with Saprol, Greenguard or Bravo. Add a
wetting agent with Super Shield and Saprol. Water either early
morning or late afternoon — in my experience this reduces the risk
of fungal problems. Come winter, prune your roses and discard
prunings and leaves that have fallen around the plants.
Plan a winter spray programme using Copper Oxychloride and Conqueror Oil to protect the plants and kill off any fungal spores that are present. Keep this up through next spring when new growth starts to develop, then swap to your usual spring/summer spray programme. Watch that the new growth doesn’t get spray burn and everything should come up roses!
Weekend Gardener, Issue 89, 2002, Page 20

