Topic: Onion White Rot

[sandersj89]

One for Tim and EJ I suspect….

I know there is not much I can do other than stop growing onions, garlic, leeks etc but can anyone give me an idea of what it is like to suffer this problem and any ways to manage it to get a crop?







These are over wintered onion sets pulled this morning on my second plot I took on last year. Leeks sown in the summer did very well but looks like the onions have been at, about 50% at the moment. Garlic looks Okish in the main. I knew the plot had club root but no one mentioned white rot.

My first plot has been fine but no alliums in that this year though leeks will follow early spuds.

 >:(

Jerry

[redimp]

Watering the ground with with water that has crushed garlic in it (when there are no alliums in the bed) is supposed to wake up white rot but it has no allium flesh to feed on so it starves to death.  This (with proper industrially prepared allium oils) has been shown to significantly reduce the incidence of white rot where it exists.  Heat also kills it so where I am going to plant alliums next year, I am going to water with garlic water (when soil temp is quite high) and if there is nothing growing there, I am going to lay black plasatic in the the hope that the midday sun cooks it to death.

[saddad]

Very interesting, I have white rot on my favourite allotment, only 5 more years before it has had it's quarantine period, must remember to do that the year before!
 ;D

[Mrs Ava]

Oh Jerry, I could cry for you!  :'(  The overwintering onions on my plot number 2 are currently looking good, however, that plot hadn't been cultivated for some years, but, of course there is always a but, I trump over plot number one, which has the dreaded rot, and then over plot number 2, so I guess I have infected that ground also.  Plus I didn't know what it was when I first took on the plot, so a lot of dodgy hunions went onto the compost heap, and back into the plot!  You live and learn.  I find the winter hardy onions are better than maincroppers, and I don't even bother with main croppers now as out of 100 sets, I would get maybe 5 useable onions.  Garlics do okay, but I find the purple/pinks seem to do better than the whites.  Shallots are 50/50.  I grew some from the garlic farm and lost the lot, but Growmore (Jim) sent me some from on 'oldie' and they were much better - probably had 75% of the crop.  He will have to enlighten you about the name and such.  Leeks seem to withstand the rot almost 100% along with spring onions.

I know I shouldn't grow alliums, but I do and I accept the losses of part of the great scheme, after all , I loose lots of other things to slugs, deer, rabbits, pigeons, the kids and so on.

I have heard that illegally watering the infected area with Jeyes Fluid before planting can help, and I understand there are legal soil sterilisers you could use, but I don't know how successful they are.  Such a shame Jerry.

[redimp]

EJ, have you ever tried watering the ground a year ahead with garlic water?  I would have thought that it was definitely worth a try with the problem you (and Tim) have with White Rot.

[Tee Gee]

You have my sympathy Jerry.

Could I ask you what type of soil you have?

Whats in my mind is poor drainage & water logging.

Why I say this is I had it(white rot) on a previous plot that was troubled with water run off from the side of the hill we grow on, yet since I moved to the lower side of the plots I have had no problems associated with water and consequently no white rot (fingers crossed)

[Mrs Ava]

I haven't RC.  It is one of those things that I know I should do, but always forget!  Also, my beds tend to be in use all year round, so as the hunions come out, something will go straight in, and as they come out the next thing will go in.  What I will have to decide is where my overwintering hunions are going to go and once the current crop is gone, try my hardest not to plant anything there and give it a go.

[redimp]

Do you think garlic water will harm standing crops?  I am just going to water and not cover if are.

[Mrs Ava]

Dunno.  Can't imagine it would...altho I would avoid the leaves of crops just in case it burns them or taints them in any way.......

[growmore]

Hammer the bed you gonna use next year Jerry with lime in autumn.I mean hammer it as in putting in plenty (lots)..Ignore the ph  it will neutralise slightly over the winter... Then lime again lightly just before you plant them out .. As EJ says  I used to treat soil with jeyes or armatillox just prior to planting .. about a teaspoon or 2 to a watering can but it aint allowed now   :)    ..   cheers ..Jim ...

[sandersj89]

Thanks all, sorry for the delay in replying but I have been away for a few days down to the farm to help out with some silaging and spraying. IFunny enough I asked our agronomist if he had any ideas and he has yet to come back to me.

To answer a few questions, the soil on my second plot is pretty good, not heavy and being at the top of the site well drained. It has been used for approx 90 years so a pest load is expected.

I may try the non legal approach.............

Jim,

On the lime approach, does this work for over wintered sets like these as well?

Thanks

Jerry

[growmore]

Over wintered sets seem to suffer more ..White rot starts when temps reach about 60 to 70 it is stimulated into action by the roots of alliums ..
As over wintered onions have a bigger root system at this time than summer ones  they seem to suffer the worst..
I have found Gerry that  liming  to excess and getting  a very  high Ph   does seem to deter it   Also onions like lime  so the high Ph doesn't seem to affect their growth  ... cheers Jim..

[djbrenton]

Just to clarify, it is perfectly legal to use Jeyes or Armillatox against white rot. All that has been barred is either company advertising it to use in gardens because they haven't paid for the testing.

[jennym]

Just to clarify, it is perfectly legal to use Jeyes or Armillatox against white rot. All that has been barred is either company advertising it to use in gardens because they haven't paid for the testing.

The law in fact does not support the above statement. Jeyes and Armillatox are not registered as a pesticide against onion white rot. Therefore, it isn't legal to use them for this purpose. They are for disinfecting objects such as concrete, woodwork, inside greenhouses etc.
All pesticides must be registered, and the Pesticides Safety Directorate is responsible for the regulations.
To quote directly from them on their responsibilities:
We are responsible for:
Providing controls on pesticides used in agriculture, horticulture and in the garden.
Monitoring the use of pesticides and take enforcement action against illegal use.
Providing policy advice to Ministers and take the lead on pesticide issues for Defra.
Supporting the UK and EU reviews of the safety of pesticides on the market.
Working to standardise pesticide regulation within Europe.
Co-ordinating a programme of research and development to complement the approvals system and support our policy objectives.
Supporting the UK and EU reviews of the safety of pesticides on the market.

They also state:
Garden pesticide products may be withdrawn from the market for a number of reasons, most of which do not concern safety:
A pesticide company may decide to take an unprofitable product off the market, or to replace an old product with a new improved product
When a company changes name, for instance after a merger, the company will need new registrations. Products with the previous company name will then be withdrawn
A pesticide company may decide not to support the pesticide through the EC review for commercial reasons, for example providing a modern data package would cost too much compared to the profits from sales of the pesticide
The EC review may show that supported pesticides fail to meet the EC standards required, and so products are withdrawn.

And they also state:
Tar Acids: the two tar acid products (Jeyes Fluid and Armillatox) are not being completely withdrawn. You can continue to use them for disinfectant pruposes, but you should no longer use them on plants after 31 December 2003.

I don't want to be seen as nit picking here, but if you apply pesticides commercially for a living, and you break the law - they will prosecute and it can be very costly for the individual in terms of money, and if pesticides are abused (which does happen although I expect the responsible type of adult that reads these pages would be sensible), in terms of health.

[sandersj89]

Thanks Jim

I will try the lime. Funny enough 2 weeks before I spoted the damage on the over wintered sets I planted out a row of onion seedlings I started off in the early spring. I will give their bed a dosing of lime tonight.

Thanks

Jerry

[sandersj89]

Well I have lifted some of the garlic, mainly Purple Wight, and it seems OK, lost about 5 heads. Still to lift the Solent Wight.



Hope it stores OK!

Jerry

[tim]

If I had one like that I would be happy!!

[supersprout]

That's a great haul jerry :o :)

[umshamrock]

AGGGGGGGGGGGGGGGGGHHHHHHHHHHHHH....

I lifted my precious garlic yesterday and every one has white rot! Now that I know what it is, I realize my overwintered Japanese onions had it too! I wondered why my onions pulled away from the soil so easily....the onions are still edible (lifted in early June) but the garlic is trash.....

So I am going to try watering with garlic water and liming....

[TEL]

I Had it bad on some of my Japanese onions to so i removed the rest Early but was lucky with my garlic