Onion White Rot -- Again!!!

[Beryl]

Catherine, I have pulled all of mine now and brought them home to finish off ripening and drying in the greenhouse. If you can do this, beter than to risk loosing them.

I know its early but then a lot of crops have been early this year.

Beryl.

[Tony Hague]

I have had some troubles with what may (or may not) be white rot over the past two years. I can't be entirely sure as I'm no expert on this, but what I have takes the form of a white fluffy mould attacking the roots and base of the onion, and sometimes garlic or leeks too, causing wilting of the foliage.

It does not affect everything, and for what it is worth, I would say:

- Multisown onions are worse affected than sets.
- Only a few of the overwintered sets of Troy and Electric Red were affected.
- Multisown Bedfordshire champion was badly affected.
- Long red Florence, though multisown in the same compost, and planted out right alongside the Beds champions, were completely unaffected (and gave a great crop).

I wonder if the congestion caused by multisowing (around 6 seed in a 2" module) creates a good environment for fungal diseases. Or if it came in the compost.

Still, I think I will not multi-sow next year, but revert to conventional direct sowing in drills. Which has the side benefit of not needing module trays or compost !

[Catherine]

Beryl we pulled ours last weekend, they are still drying in the PT I have put all the dodgy ones at home and the rest are drying. Lots of people have lost theirs on the allotments. I am going to look into what to grow next year as we lost all our shallots this year to this disease.

[Stephen]

Asking around, several people on the same set of plots have suffered, although some took a bit of convincing that that is what the problem was. I'm glad I got mine up early and processed. The unaffected ones appear to be storing well.

[Stephen]

BTTT as this was talked about on Gardeners Question Time last Sunday (it was from Scunthorpe). One plotholder kept white onion rot at bay with chimney sweeps soot (whoch he weathered for 6 months before use). He was mixing with lime. (I wouldn't sdd the lime as I am on chalk).
What do the combined experience of KG message boards correspondnts offer on this?

[realfood]

I have not tried it but soot, if from coal burning would be toxic and I would not want to add it to my soil. It would contain all sorts of coal tars which might have an anti fungal effect similar to Jays fluid, but not a good idea!!

[Stephen]

I would have thought the same but the gardener interviewed was quite clear and had been doing this for years. Weather it for six months before using it.
This was an interview on the allotment site and there was no comment from the panel subsequently.
The programme will be available for only another day or two.
I am tempted to write and ask.

[Kleftiwallah]

I just called into my favourite garden centre on my way back from the market and told them (as I had bought the shallots and onions from them) I had white rot on the allotment and has anyone else called in.

The mature female said that she had heard it from lots of people that they had it also, but didn't say her sets were to blame. Must just be a countrywide problem. Still waiting to hear a reliable antidote. . . . Cheers, Tony.

[Beryl]

Even if you don't grow onions in the same place each year, just by walking on the soil can spread it elswhere. Removing all the infected soil is the only way to avoid it. Not easy, unless you confine your onions to a raised bed and renew it every year.

Not sure if onion sets have to be certified disease free the same as spuds. Anyone know?

Beryl.

[realfood]

Klefti, have you thought of using the garlic water solution that was very good for me this year?

[Beryl]

Very good informative article in Nov. TKG.

Beryl.