I Have Apotted Hydrangea Which Has Developed A Greyish White Leaf Colour,. Lots On New Growth Come Through Below

Question

Don,t know what this is or what to do about it. would be very grateful for your advice. Plant id in ericaceous compost . Thanks

Answer 1

It may be powdery mildew, triggered by either a normally very humid environment, by overwatering or by overhead watering. Control high humidity levels. Use a fungicide or make your own spray. Stop after the plant goes dormant and drops leaves but resume when there is leaf out or new stem growth.