Plant Doctor Archive

Azaleas

We have several old azaleas which have been pruned hard, as they were quite straggly. The resulting new growth was good, but all the new leaves are now completely brown with rust and look most unattractive. I have sprayed them with every spray that I thought appropriate, as well as Jeyes fluid, Thrive, seaweed solutions, Nitrosol, Phostrogen, trace elements - you name it. I will be grateful to have your advice regarding this problem.

START by removing any fallen leaves from the ground under your plants. These may be providing a source of reinfection. Spray with copper or Saprene as the new leaves form in spring. A simple green method of control is to scatter the ground under the azaleas with flowers of sulphur, while building up the soil by adding plenty of well-rotted compost at the same time.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.