Lime sulphur spray is used as a fungicidal treatment and preventive for a wide variety of both edible and ornamental trees and plants. It's an older treatment that has fallen out of favour due to many newer fungicide formulations. Although fungus is effectively controlled with the lime sulphur spray, the mixture often stains plants white and can burn the leaves of fruit trees if too much is applied at the wrong time. To prevent damage, mix the lime sulphur with water to the proper dilution level.
Unscrew the top from a garden sprayer and put on gloves before adding in 170gr. of lime sulphur. Lime sulphur is available in both liquid and powder form at garden centres and at some home improvement stores.
Dilute the mixture with 1 gallon of water. Place the cap on top of the garden sprayer and shake it up well to mix the two ingredients together.
Remove the top from the garden sprayer again and pour in 88.7ml. of a horticultural oil. Horticultural oil helps the lime sulphur mixture stick to the leaves instead of washing away.
Replace the garden sprayer top again and shake for 10 to 20 seconds to mix all of the contents well.
Lime sulphur spray is best applied in the very early spring when the trees or plants are still dormant. Apply the lime sulphur spray when temperatures are lower than 26.7 degrees Celsius, since leaf damage occurs at higher temperatures. Always wear safety glasses when applying lime sulphur spray since the substance is corrosive.
Do not use lime sulphur spray on apricot trees and don't apply it to plum trees when they have leaves.