glenn mahon asked 14 years ago
I have used a mixture of washing soda and blue stone on my potatoes to prevent blightbut i am not sure how often i should spray them
1 Answers
Gerry Daly Staff answered 6 years ago
Burgundy mixture works by the copper in bluestone preventing the fungal spores from growing. This gets washed off and the need to repeat-spray depends on the amount of rainfall and the rate of growth of the plants, new unprotected foliage being produced.
It might need to be sprayed as often as every two weeks in rainy weather.
