Description:
Although rust is widespread, it is most consistently
a problem in Western states.
Symptoms:
Yellow “rust” spots appear on the topsides
of leaves during cool weather in spring or
late fall. Infected leaves become twisted and dry.
Spores infect leaves when rain, dew or fog occurs
at temperatures from 55° to 75°F.
Solutions:
When rust is first noticed, pick off and
destroy infected leaves and spray plants with a
copper soap. Repeat sprays every 7-10 days as
long as conditions favor rust infection. Remove
and destroy diseased leaves and twigs in the fall.
We recommend Soap-Shield Flowable Liquid
Copper Fungicide.*
*NOTE:
Soap-Shield may cause copper toxicity
on some rose varieties. Copper toxicity appears as
purple spots and is more likely to occur outdoors
than in greenhouses.