This time of year at the beginning of June if you have plum trees it is very important to remember to carfully check the young slowly forming fruits for any signs of plum pocket. I did this job this week – I love observing my new fruits – who doesn’t? – and I carefully cut off any deformed specimens from my plum tree and placed them in a paper bag for burning later on – I don’t like to risk composting when it comes to fungal diseases!
I must have absentmindedly placed one of them in my pocket because when chatting to a friend later on that evening I fished one out of my pocket along with my handkerchief! Upon sight of the deformed fruit my friend cried “aha so even great horticulturists (sic) suffer from bent banana disease!” I’d never heard Taphrina pruni (“taphre” is Greek for a ditch) referred to in this way – my mother always called it plum pocket – bent banana disease certainly put a smile on my face – somewhat countering the frown generated when I spotted the fungus lurking among my baby plums!
How to treat plum pocket
There is no propriety chemical treatment available to the amateur gardener in the UK. Interestingly when we were still burning lots of coal here in the UK this disease along with many other fungal plant diseases (buxus blight, black spot on roses etc) these diseases were far less common and even if there was the occasional out-break these were less severe. This was all due to the notorious acid rain caused by the sulphurous fumes pumped into our atmosphere by our belching coal smoke chimnreys. The sulphurous acid rain did have one advantage that it killed off many of these common garden plant fungi. You won’t be surprised to learn then that one of the sprays available to commercial fruit growers is a sulphur based anti fungal.
Since Taphrina pruni is not fatal to your plum tree you needn’t worry too much at the lack of chemical treatments. The key is to look out for early signs of diseased fruits and to carefully remove and destroy them preferably by incineration. The infected plum pictured above was already at quite an advanced stage of infection and was therefore very easy to identify. If you can identify them earlier this would be better – the first telltale signs are small innocuous looking spots which quickly develop into larger blisters.
Keeping good gardening hygiene regime is key to minimising all fungal diseases.