What fertilizers do they use.Flowering or winter and how can I keep downy mildew at bay. I am currently using Physan 20 when I feed them(once weekly)?
Fertilize with caution. A light (cut in half) application of a balanced fertilizer every few weeks during active growth. Flush the soil every so often to avoid excess fertilizer build up.
This link has information on the control of Downy Mildew