White onion root rot or other onion rot?

[Terryr]

Hi all, best wishes for the Festive Season.
I have a little question that might be difficult to answer.
For years I have had great difficulty growing onions in my garden because I loose lots of them to fungal rot. I had assumed that this was white root rot which is a pernicious disease. However, I wonder if it a some other form of rot linked to heavyish soil and wet conditions. Can any of you out there tell the difference?
I am sorry if I keep returning to this theme but it really gets my goat.
Regards
Terry
Be good to gardeners.

[Snadger]

H Terry

I too have struggled with onion white rot and have wondered whether it is related to the soil type.

I had a couple of beds where my onions, shallots and garlic succumbed to the white rot fungus. After alliums I thought I would try brassicas in the same area and these succumbed to clubroot! Both are fungal diseases and I am pleased that you can now get clubroot resistant brassicas but didn't realise you could get white rot resitant onions. Onion Golden Bear is sold as 'white rot resistant' so I have procured some seeds and may give a few a try in the troublesome area in 2009.

My soil is a well manured dark silty loam all over my plot but the white rot only appears to be prevalent in one area. I imagine sandy soils wouldn't suffer to the same extent, but aint sure about this?

[Terryr]

Hi Snadger

Very interesting observations about your plot. For my part I can grow shallots and leeks without any trouble. These tend to be actively growing during then colder parts of the season. I found out on-line that OWRR needs a certain degree of warmth to activate it. However, I am still not sure about it all?
I will also try Golden Bear, I noted in the Organic Seed catalogue that there were claims of resistance. Incidently, I tried the clubroot resistant cabbage myself this year and I have the best heads ever.
Regards

Terry

[Two_Sheds]

I imagine sandy soils wouldn't suffer to the same extent, but aint sure about this?

I'm practically on the beach, and I got White Rot in half my crop this year. Never had it before.

[Snadger]

Hi Snadger

Very interesting observations about your plot. For my part I can grow shallots and leeks without any trouble. These tend to be actively growing during then colder parts of the season. I found out on-line that OWRR needs a certain degree of warmth to activate it. However, I am still not sure about it all?
I will also try Golden Bear, I noted in the Organic Seed catalogue that there were claims of resistance. Incidently, I tried the clubroot resistant cabbage myself this year and I have the best heads ever.
Regards

Terry

Funny you should mention white rot being temperature reliant, I have managed to grow spring cabbage and winter kale with no clubroot problems and have always thought clubroot......another fungal problem, was temperature reliant!
Of course kales have a tight cell structure (hence walking stick kale) which gives a natural resistance to clubroot...........I also believe that all the new clubroot resistant brassicas have kale somewhere in there lineage!

[zazen999]

I was going to suggest adding sand or loam...Two_sheds were they from sets or seed?

I've only had it in sets thus far...and have also bought Golden Bear seed to try this year. Luckily we don't get much rot but I want to try the Golden Bear seeds in the place where we have had it.

[Snadger]

I'm practically on the beach, and I got White Rot in half my crop this year. Never had it before.

Ah well............that's put paid to that theory then.!

One thought though........you've only had white rot this year for which you blame some dodgy onion sets from W****'s? I put it to you that because the white rot was carried on the sets it would have flourished whichever soil type you have? That being the case it will be intersting to see if your plot is infected badly THIS year?
I would try a few in that area.................just to prove me wrong if nowt else!

[Two_Sheds]

Yes Snadge, they were sets from W1lko. Not all the varieties were affected, and my seed-sown onions (Keepwell) didn't get it.
So I deduce the sets were to blame.

This year I am growing onions from seed, and shallots from a different supplier (if they ever arrive ... I think the postie's nicked them. He's also nicked our Bratz wellies and Winnie Pooh dinner set )

[gojiberry]

First year I have had white rot and it was in seed sown onions. I thought it was maybe due to being transplanted into a peat based compost before being planted into lottie and that the peat had just retained to much water underneath the bulb. Will be trying potting on mix with sand or sharp grit this year to see if it makes a difference. Will be starting the seed of this week. Can't remember what at moment but have built up a good supply and variety of onions to see what does best. I know one is long red florence as the packet is still next to the pooter.


Ian

[Snadger]

........................................ I know one is long red florence as the packet is still next to the pooter.


Ian

Funnily enough, I have had quite a bit of success with this tasty onion.....

[Two_Sheds]

here's last year's thread: http://www.growfruitandveg.co.uk/gra...rot_14624.html

[Snadger]

Maybe a sheen flame gun could get the soil hot enough to burn it out..........half a dozen shovel fulls on some paving........blast it with the paraffin flame gun until it's really hot.......bag it and move on to the next half a doz shovelfuls?
A lot of work I know, but should have the desired effect?

You could just use it directly on the soil but the temperature wouldn't penetrate more than an inch or two!

Small amounts can be done in the microwave........but don't let OH catch you!

PS Another way would be to light a funeral pyre from used timber then cover it with soil and let it cook! Bit anti social though as it would generate a lot of smoke!