Keep an eye on your Brassicas - lots of Diamond Geezers about

On Saturday night I set my moth trap out in the garden, as the night looked set to be warm and still - not something we have experienced much of lately.

In the morning I was amazed to find the outside of the trap covered in little Diamond-back moths! On opening the trap, clouds of the tiny creatures flew out and the egg cartons (where the moths hide in the trap) were covered with yet more.

A Tiny Diamond -back MothA tiny Diamond-back moth - only around 7 or 8 mm long! 

By the time I had finished examining the catch - a rough guesstimate was that I had caught around a 1000 of these little migrant moths.

Despite their minute size these micro moths travel to our shores from the continent and then have several broods during the summer. It is quite normal to have catches of double figures in the late summer - but a 1000 moths so early in the year is incredible.

The reason I have titled this blog so, is that the food plant of Diamond-back larvae is brassicas of all sorts. So you gardeners and commercial veg growers beware - we are being invaded big time!

Free GWCT Newsletter
Get the FREE weekly GWCT newsletter

Get all of Peter's and the GWCT's latest blog updates sent straight to your inbox each week.

Sign up to our FREE newsletter >



Diamond-back moths

at 9:44 on 30/06/2016 by mairi macdonald

I have a coastal plot in the North-west highlands, Applecross, and my 3 varieties of kale (black, red & russian) all have been decimated by this moth this year. I normally grow from seed and have previously had no trouble with pests whatsoever, but for reasons of convenience I bought some of my seedlings from a garden centre in Inverness this year - whether this is how I imported the moth I do not know, but I am very concerned about what to do to prevent them doing the same next year. Any suggestions out there?

Diamond-back moths

at 10:37 on 09/06/2016 by ALAN E DOWN

Co-incidentally we have noticed lots on our hardy nursery stock crops this week [Bristol] but fortunately we grow very few Cruciferous species. What would have been useful in your briefing would have been some suggestions on how one controls this important pest. It appears to have the ability to be a very serious pest and apparently has resistance to many pesticides but more surprisingly to the biological control agent Dipel [Bacillus thuringiensis]. Any thoughts please.

Diamond-back Moths

at 20:31 on 08/06/2016 by Tim Brain

Here in Kinross-shire, Cental Scotland, I am getting up to 20+ a night, so they have probablely travelled a further 300 to 400 miles!!

Make a comment

Cookie Policy

Our website uses cookies to provide you with a better online experience. If you continue to use our site without changing your browser settings, we'll assume you are happy to receive cookies. Please read our cookie policy for more information.

Do not show this message again