Grey Mould (Botrytis) on Fuchsia Stem?

The furry substance on this fuchsia stem looks like Grey Mould (Botrytis cinerea) thriving on sugars in the sap which is still bleeding from the cuts I made last week. It has run down the stem and is keeping it permanently wet. And, since the fungus threads (hyphae) now seem to be entering the internal tissue, the outcome could well be fatal - little can be done apart from removing the infected part and hoping for the best.

Botrytis is probably the biggest disease problem in cold, humid growing rooms (especially greenhouses). The problem here is that the compost was too wet at the start. Had the weather been a bit warmer, it would have dried things up a bit, so I might have got away with it. In fact, if you look carefully near the tip, you should see a new red bud developing; it almost made it.

This disease is particularly dangerous to weakened plants such as this triphylla fuchsia (because we trimmed its roots and cut off all its leaves), especially during winter storage.

This is why I am usually so fastidious about keeping compost and plants as dry as possible (and free of old loose dead plant material, which is where it is usually first noticed.


Some of you might have thought my treatment of overwinterning geraniums a little severe.


But, like fuchsias, they too are highly susceptible (never keep the geranium stems wet in winter - if you have to water, do so by standing the plant in a saucer of water for 15 mins) to botrytis.

Most books will tell you to cut plants back before storing. I have had a problem with this disease every time I have done this. And I try never to water them till growth commences in the new season. Once this occurs, Botrytis loses its potency.

To help avoid the disease, remove all dead material (e.g. leaves) from top of the compost, so it can't get a hold, and give plenty of fresh air. You can use a contact fungicide such as mancozeb (e.g.'Systhane') to help prevent infection. But note that you must treat the whole plant, since contact fungicides cannot enter the vascular system in the same way systemic ones can. But they do kill a wider range of diseases.

I have dusted the fungus with sulphur powder, because I don't have any 'Systhane'.

Of course, there is a possibility that, if the plant dies, it will will be more to do with cutting it back too far. I don't think so. Have a look at this.