Onion White Rot

[cornish crabber]

My onions, grown from sets, were doing very nicely. But today I found some were keeling over. I've dug these up and found the dreaded white rot.

Is there any hope of preventing the rest of them going the same way? A friend has suggested Bordeaux mixture, but there's no mention of white rot on my bottle of it.

My books say there is no cure and I have to avoid growing onions on that patch for either 8yrs (Dr Hessayan) or 20 yrs( Readers Digest)!!

I'd be grateful for any advice

[always digging]

thats really bad and yes it takes years for the white rot to go just dont grow any onions on that spot all the best

[zazen999]

There are 2 ways to grow onions on an area that has had white rot; as long as you give yourself an expectation that you WILL lose some.

a - they are currently investigating whether spraying with garlic spray and leaving it a few weeks before planting out your onions will work and be able to be made into a solution; the theory is that the garlic releases the spores into action but being there are no onions there to work on, the spores die.

b - dig the bed over, and add sand; lots of it. And try to keep it really dry. I did this over winter with a bed of clay that had previously had white rot and hardly got any - I cloched them and added a bad of builders sand and it worked a treat. I only got white rot on a tiny amount, and it was well worth it!

Or just grow more and expect to lose some - if you build it into your expectations then you won't be disappointed.

[cornish crabber]

Thanks zazen999, good to think all is not lost. Will certainly try these ideas

[Snadger]

Or try Golden Bear onions! They are supposed to be white rot resistant. This was true of mine last year, although they were very small.
Sowed them early this year and they are much bigger plants at this stage. Fingers crossed for a good clean harvest!

[The Large One]

Sorry to bring up an old thread

first real crop we sowed into our first allotment was shallots and recently i had to pull them all and dump
i checked on the internet and found that it was white rot and thought...booger.
When we took on the allotment i was told there were no real problems on the site but now next door neighbour says white rot is "quite bad here"
so much so that he has taken to growiing his onions in pots which are filled with sterile soil "not from the plot" and last week he lifted a couple to see and all looks very very promising


Question i have though is
i read somewhere that seeds maybe better against white rot than sets, is this true ?
i have already bought some shallot seeds, they were on sale in the local GC so i'm going to try them next time

Nick

[OllieMartin]

Anyone got any images of a white rot infection, which aren't copywrited (copywritten...copywritatized? )

I'm trying to update the white rot page:
Onion white rot - WikiGardener Wiki

[womble]

Or try Golden Bear onions! They are supposed to be white rot resistant. This was true of mine last year, although they were very small.

Hey I didn't know there was a WR resistant onion!

Good to know, I can grow onions again with no worries, anywhere I like!

Please please please, can someone bring out WR resistant garlic and leeks now

[oldie]

I found I had white rot last year. For a number of reasons I had already decided to sow a large area including the onion bed with Bio-sterilant mustard I think some sell it as calientelle(sp?) mustard. I got mine from Victoriana nursery and followed the instructions carefully. Bad planning on my part meant I had some sets left over this year so I stuck them in that area. So far no sign of white rot so far. I would hesitate to draw any conclusions but it may be worth another trial.

[Snadger]

Hey I didn't know there was a WR resistant onion!

Good to know, I can grow onions again with no worries, anywhere I like!

Please please please, can someone bring out WR resistant garlic and leeks now

I have a rather nice bed of GB fattening up well. Unfortunately one of about 30 have succumbed to the dreaded white rot, so it looks like 'resistant' means resistant and not immune! Watch this space.

[womble]

I have a rather nice bed of GB fattening up well. Unfortunately one of about 30 have succumbed to the dreaded white rot, so it looks like 'resistant' means resistant and not immune! Watch this space.

One of 30 are odds I like the sound of. Watching with interest.

[Two_Sheds]

they are currently investigating whether spraying with garlic spray and leaving it a few weeks before planting out your onions will work ...

Bob Flowerdew was saying much the same thing a few weeks back on GQT: except that he said to put the white rotty onions back on the bed to rot down.

I've been growing onions on the same patch for the last 2 years despite white rot, and the harvest isn't as bad as I'd expect. I lost a whole row of Red Baron sets (Wilko) to it this year, but the other 2 rows were fine, and most of the other 8 rows are fine too.

[Snadger]

Bob Flowerdew was saying much the same thing a few weeks back on GQT: except that he said to put the white rotty onions back on the bed to rot down.

I've been growing onions on the same patch for the last 2 years despite white rot, and the harvest isn't as bad as I'd expect. I lost a whole row of Red Baron sets (Wilko) to it this year, but the other 2 rows were fine, and most of the other 8 rows are fine too.

Don't understand the logic there. Surely this will just feed the white rot and help it prosper?

[Two_Sheds]

Well, the theory is that the white rot spores do their thing on the soil and die out, before you plant your next lot of onions. Or something (science tends to go over my head tbh)

[Snadger]

Well, the theory is that the white rot spores do their thing on the soil and die out, before you plant your next lot of onions. Or something (science tends to go over my head tbh)

I can understand the logic behind the spraying with garlic water theory as the spores won't have a host to latch onto. Fair enough, but to put affected onion waste on land will mean the spores multiplying on the host plant, completing their life cycle, lying dormant in the soil, then even more spores/mycelium will be ready to attack the next allium crop. Or am I missing something?