Can you use pest oil on both Mandarin and Orange Trees that are in flower now (October) as the leaves have a blacky soot cover on them which I wish to clear up.
07 October 2012 12:18 PM
PestOil can be sprayed on citrus during October even when they are flowering. It is not recommended to use PestOil on the Glen Retreat mandarin variety. Spray in the late afternoon avoiding the hot part of the day. Spray both the leaves and the branches as the scale are probably on both parts of the tree.