Onion white rot

[treepixie]

Just lost my entire bed of autumn sown onions, is it to late to do some from seed?

[Snadger]

Probably a bit late for seed but you may get a crop with sets?

[Thelma Sanders]

Yes, I'd try some sets in another bed, of course, and remember never to plant onions, garlic or leeks in the bed where the white rot is. Once you've got it there, it just sits waiting for the next allium crop to start up again.
I hope you haven't got it in every bed, like I had on my old plot

[Chestnut]

I had that same problem a couple of years ago.
Probably a bit late for onions from seed, and as Thelma says there’s the risk it’s across the whole plot, so maybe worth hedging your bets and just plant a small number of onions from sets, then fill the rest of the space with something from another plant family that’s well suited to later planting? Pumpkins perhaps?

[treepixie]

Thanks, I have a pack of onions I got reduced, I will plant them in another bed, and hope for the best.

I took on this allotment last year it’s all raised beds, it’s my second one, so hopefully not all the beds have it.

At least I have more room for my tomatoes

[ameno]

I don't know how well it works on all sites, but I read in the Which Gardening magazine a few years back that planting your onions/onion sets in 9cm pots of compost with the bottoms cut off, then planting those as-is (pot and all) in the ground once the onion has grown a bit, making sure the soil never touches the bulb or leaves, works really well in soil contaminated with white rot.
You would need to use fresh pots or else sterilize your pots each year, though, as white rot may persist on the surface of the pot.

[Mr Bones]

Too late for this year but Golden Bear from seed are very resistant to white rot.

[Derbydal]

plastic cups should /could do it .atb Dal

[Mark_Riga]

Also with white rot, space onions at least 6" apart as the fungus will travel along the rows otherwise. You then need vigilance to remove infected plants ASAP, not easy but pulling fairly gently and if get movement then remove. I doubt it can persist on pots as, in soil it is black pinhead sized bodies called sclerotina or something that are formed and can persist in the soil for years.
I've got 2 areas I grow veg in one with white rot. I grow autumn planted onions there as they are ready that much sooner and escape the worst of the disease which tends to strike from late May. Picture is a small onion pulled up 2 days ago. It's been cleaned up a bit but would rot quickly. The black at the end is likely place for the sclerotina to develop I think and will be cut off and binned. The rest will be eaten soon.
Also a snap of the onion bed with gaps where suspects have been removed and used.


This autumn onion plot is looking a bit wet today and the sweetcorn/squash planted out in it are drowning I think - unlike last year.