Rob Smith had a sur­prise with his onions!

I’m work­ing hard to deal with the ef­fects of dreaded fun­gal dis­ease

Garden News (UK) - - News - ROB SMITH

As the days be­come shorter and the tem­per­a­ture starts to drop, I’ve been dodg­ing rain show­ers on the al­lot­ment, try­ing to get jobs done. One thing I’d for­got­ten to do was dig up some of my re­main­ing onions I’d grown from seed – I never seemed to have a fine day to let them dry out on the top of the soil. When I did get around to dig­ging them up, I was greeted with a nasty sur­prise – onion white rot ( Stro­ma­tinia cepivora). This fun­gal dis­ease af­fects most of the ed­i­ble al­lium fam­ily, in­clud­ing gar­lic, leeks and, of course, onions, but fun­nily enough ele­phant gar­lic doesn’t seem to suc­cumb as eas­ily to the dis­ease.

You can tell if you have the dis­ease as your onions will have droop­ing, yel­low­ing leaves and the bulbs will feel loose in the soil if you give them a wob­ble. When har­vest­ing, you’ll see a white, fluffy sub­stance on the bot­tom of the bulb and you’ll get a smell of rot­ting onion. You’ll then have to burn the af­fected bulbs, and if that wasn’t bad enough the fun­gus can stay dor­mant in the soil for 10-15 years, mean­ing you shouldn’t grow al­li­ums there again!

The fun­gus is eas­ily spread by tools or on your footwear, so be care­ful you don’t spread it all over your plot. There are a few things you can do to carry on grow­ing onions. Firstly, grow them in an­other bed or in a raised bed with new soil. Se­condly, you can wa­ter the bed ev­ery month with gar­lic wa­ter (five crushed gar­lic in two litres of wa­ter left overnight). The fun­gus can only ger­mi­nate once be­fore dy­ing, so fool­ing it to grow when there are no bulbs for it to af­fect with this dummy wa­ter so­lu­tion can re­duce the prob­lem. It won’t af­fect other plants, so you can still grow things in the bed while treat­ing it. You can also grow ‘Caliente’ mus­tard (avail­able from Mar­shalls, www.mar­shalls-seeds.co.uk) as this green ma­nure is a bio-fu­mi­gant, which can con­trol dis­ease. Make sure to chop the mus­tard up very small and bury it within 20 min­utes to get max­i­mum ef­fect from the gasses given off. I use a ro­ta­va­tor for this. None of th­ese meth­ods will fully cure the prob­lem, but I’m hop­ing it will re­duce the ef­fects of the fun­gus on my plot next year.

I was shocked to find white rot on my onion crop

Fluff was a tell-tale sign my crop was in­fected

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.