Jean from Heyworth, Il writes
Bonide Liquid Copper Fungicide Concentrate is not labeled to be used on impatiens.
According to this article by Wisconsin Horticulture County Extension Office, it states: "DO NOT use fungicides on plants that are showing symptoms as such treatments will not be effective. If you see impatiens downy mildew, remove symptomatic plants (roots and all), place them in sealed plastic bags and throw them away in the garbage; DO NOT compost these plants. Also consider removing all impatiens within a three foot radius of symptomatic plants. These plants are likely infected, but not yet showing downy mildew symptoms."
We would also recommend contacting your Cooperative Extension Office to see if they've had any success with any other specific products.
Answer last updated on: 08/26/2021
