Topic: Onion Rot

[tim]

For want of any other advice, I use Armillatox.

[Tin Shed]

Thanks, Tim

[shirlton]

Well folks here are some pics of other peoples onions, some have used manure others have not. Japs havent been affected, they have just run up to seed due to the weather. All these pics are of spring sewn sets. I have done some pics of spliced bulbs and on the last one which is a shallot ther was a tiny slug anda few tiny white maggots. If you blow the last pic up a bit you will see it at bottom left of the shallot

[tim]

Well, at least there's no sign of white rot.

[BAK]

Re pictures above ...

not convinced, ie speculating ...

but what about stem and bulb nematode? (mainly from the stem distortion).

You need an expert view really.

[Tee Gee]

I'm sticking to my original statement...........I think it is Onion fly more so now that you have found a maggot.

I think it is a bit early in the year but I think 'global warming' has something to do it.

When you think the weather in April was warmer than some July/August weather of the past,( the time I would expect onion fly) 

The fly doesn't know if it is coming or going and if you have planted out sooner than usual then ideal conditions were quite probably produced.

What I think regarding the twisted leaves is; and this is only an opinion, the fly got into the young growth( at the neck of the set) before the leaves matured and it affected them.

Normally I would expect onion fly to be much later i.e. when the onion leaf system is more mature and consequently less likely to be affected as much, if at all!

In normal years the signs of the flies presence is more likely to be wilting of the leaves as the root system and base of the onion/s is eaten away by the maggots.

I am aware that eelworm has similar symptoms but there was no sign of them in the stem!

Just as a matter of interest when did you plant out?

In my case I did not plant out till the 5th of April which was the start of the warm spell so my conditions were not similar to yours.

There is one consolation; I am fairly certain it is not Onion White rot!!  so at least your ground won't be contaminated.

As I said this is only an opinion based on experience/s

[shirlton]

Thankyou so much for the advice TeeGEE. I'm pleased that it isn't white rot. What you said about the warm weather makes good sense. We planted them out in march. I have noticed that a couple of folks on both of our sites were late in planting theirs and they don't seem so bad.Do you think that it's worth growing them under enviromesh if we get another Spring like this next year or is there some other deterant.

[shirlton]

What if anything could be planted in the position when the onions are removed. Cucumbers?

[Robert_Brenchley]

Not a sign of rot there. I'm inclined to put it down to the peculiar weather, and if you're finding maggots, then it could well be onion fly.

[shirlton]

For want of any other advice, I use Armillatox.

Thanks Tim. I have some Armillatox thats in a plain bottle that I got from the shed. What strength do you use and how long after can the area be replanted.

[Tee Gee]

Do you think that it's worth growing them under enviromesh if we get another Spring like this next year or is there some other deterent.

Personally I would plant them later but I see no reason why you can't cover them.

Oddly enough I covered mine this year with fleece but not for 'fly protection' in my case it was simply to keep the cats off the bed.

What if anything could be planted in the position when the onions are removed. Cucumbers?

Are we talking Summer or Autumn sown onions?

I generally follow my Autumn onions & garlic with winter greens.

After the summer onions I winter dig & muck spread the bed............too late to put anything else in!!

[shirlton]

I'm intending to get these infected onions up as soon as possible and didn't want to leave the ground empty until the end of the year or next year. I thought maybe I could get a quick crop of something. I am going to put the onions somewhere else anyway in future just in case and I will probably cover them.

[davyw1]

I would have thought like Tee Gee about onion fly being early but that looks as if it what you have.
Also i don,t think putting fresh manure on an Onion Bed is a good idea.
When you come to get them out remember that not all you onions will be infected with it.
Picture of what you onions look like when infected by the fly, compare this to your onions

[saddad]

My top Plot has white rot... so not grown any alliums there for five years... going to give it at least another five... but they didn't look like that..
If it isn't hormone (weedkiller damage) I don't know what it is... Do the council weed spray the avenues? you may have caught some drift!
 :-\

[shirlton]

Well folks the secretary has suggested that everyone on the site who has onion fly gets them up and gets rid for the sake of the plot holders who haven't got it. Glad to say all have taken action. I doubt very much wether the folks on our other site will be willing to do the same. It's great when everyone works together isn't it.

[Robert_Brenchley]

Somebody on my site suggested this might be leek leaf miner. Whatever, it's definitely some horrible insect.