Spider mites, psyllids and thrips also are susceptible to sulfur. Most pesticidal sulfur is labeled for vegetables such as beans, potatoes, tomatoes, peas and fruit crops such as grapes, apples, pears, cherries, peaches, plums and prunes. Sulfur has the potential to cause plant injury in dry 90 degree-plus weather. It's also incompatible with other pesticides. Don't use sulfur on plants within 20-30 days of applying spray oils.
Sulfur reacts with the oil to create phytotoxicity.
Sulfur is non-toxic to mammals, but it may irritate eyes and skin. Lime Sulfur Lime sulfur is made by boiling lime and sulfur together. The mixture is used as a dormant spray on fruit trees to control diseases such as blight anthracnose, powdery mildew and some insects including scales, thrips and eriophyid mites. It was used first in Bordeaux, France to control downy mildew, hence its name. Bordeaux mixture is primarily a fungicide that controls bacterial leaf spots, blights, anthracoses, downy mildews and cankers.