[MalcW]

Apparently, according to the BBC, our brassicas are under threat from swarms of these moths. See http://www.bbc.co.uk/news/science-environment-36516619.

Mine are already under threat from pigeons and slugs...

[New shoot]

Crikey, that's a bit doom and gloom isn't it 

Mine are already under threat from pigeons and slugs...

Mine too ..... maybe I don't need to worry about the moths 

[grinling]

It will be a huge problem for the farmers who grow as without a product they don't get paid and I know a few who produce this crop.

Easy to protect from birds and slugs, but so much harder from the moth

[New shoot]

This is interesting.  Apparently the adult moths that are around now may be the offspring of an influx we had earlier in the year. 

http://www.nhm.ac.uk/discover/diamondback-moth-epic-journey.html

Although the media is just picking up on the story, it seems the latest outbreak actually started in the first week of June, so rushing out with the environmesh may be futile now.

[sunshineband]

That is interesting New Shoot, as we seem to have had them around for a few weeks - debris netting keeps them out! I didn't know what they were called until the media "announced" their arrival yesterday.

[AnneB]

I found a few of these on my peas the other day.  All my brassicas are under enviromesh netting that has been in place since I planted them out, so hopefully they will be safe (but not from the slugs!).   

The articles here imply that it is 'mainly' brassicas that are affected.   Do they go for anything else?

[mumofstig]

Wiki is helpful for a change

The diamondback moth (Plutella xylostella), sometimes called cabbage moth, is a European moth believed to originate in the Mediterranean region that has since spread worldwide. The moth has a short lifecycle (14 days at 25 °C), is highly fecund, and is capable of migrating long distances.[1] It is one of the most important pests of cruciferous crops in the world and usually only feeds on plants that produce glucosinolates.[1] However, not all of these plants are equally useful as hosts to the moth; a 2006 academic paper suggested using wintercress as a trap crop around agricultural fields, [2] as diamondback moths are highly attracted to that plant but their larvae fail to survive when eggs are laid on it.

If they don't like cool weather, I can't see them lasting for long 
https://en.wikipedia.org/wiki/Diamondback_moth

[sunshineband]

Since making that debris netting cover, we have found quite a lot sitting on the outside of it. Obviously they "went West" as the saying goes. They must be attracted to the smell of the brassicas: I guess the glucosinalates do this?

25degC seems a bit optimistic round here though. I wonder if freezing weather will kill them off?

[Salmo]

I found a few of these on my peas the other day.  All my brassicas are under enviromesh netting that has been in place since I planted them out, so hopefully they will be safe (but not from the slugs!).   

The articles here imply that it is 'mainly' brassicas that are affected.   Do they go for anything else?

If they are on your peas they could be pea moths.

There are many tiny moths. The diamond pattern on the back is distinctive.

http://www.wildlifeinsight.com/diamond-back-moth-plutella-xylostella/