Q.Plant loss (begonias) from Pythium?
I am only a home gardener and I grow a large number of begonias and over the past couple of months I have lost over 50 plants. They include mainly cane-like and rhizomatous types and they grow in different areas i.e. shade house and patio. I think it is a fungus/pathogen root rot type of problem and I have no way to stop it from spreading from plant to plant, my plants start off looking sad, droopy leaves, soft/rotting rhizomes and also may have mealy bug which I can treat. I do not over water my plants and practice good plant hygiene. I belong to a society but their help has been limited. I have read your section of Treating Root Rot but the problem persists. I have used different fungicides Anti Rot and Eco Fungicide. Once a plant is re-potted it seem to be even more susceptible to rot. I am very upset and looking for any advice that may help. Mainly I want to know how to stop it spreading. Removing affected plants does not stop the rot appearing in other plants.
Certified GKH Gardening Expert
It may be botrytis blight. Here is more information and how to control it. I also included info about pythium rot.