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Produce => Pests & Diseases => Topic started by: caroline7758 on May 04, 2013, 17:05:17

Title: Non chemical cure for bean weevil
Post by: caroline7758 on May 04, 2013, 17:05:17
My first row of broad beans look as if they've been attacked with pinking shears! I guess this is bean weevil- never had it before. :(
Is there anything I can do to save these plants and avoid the next lot getting attacked?
Title: Re: Non chemical cure for bean weevil
Post by: Robert_Brenchley on May 04, 2013, 17:21:44
Sure it isn't flea beetle? If it is, they cease to be a problem as the plant gets bigger. I never bother about them.
Title: Re: Non chemical cure for bean weevil
Post by: caroline7758 on May 04, 2013, 17:24:52
How can I tell the difference, Robert?
Title: Re: Non chemical cure for bean weevil
Post by: Ian Pearson on May 04, 2013, 18:27:19
If the holes are u-shaped round the edges of the leaves, that's bean weevil. Not usually fatal unless severe, but the larvae attack the roots, and can weaken the plants.
It's possible to catch the adults by hand. Best on a windless day, stealth and good eye sight required. Sometimes they play dead, so don't be fooled. I've heard of folk having success with homemade insecticides such as rhubarb spray.
Title: Re: Non chemical cure for bean weevil
Post by: galina on May 04, 2013, 18:27:56
Just checked on the HDRA/Garden Organic website.  And they suggest to do nothing.  Usually plants shrug it off.  Just give the plants the best growing conditions.

If you save your own seeds, dry them very carefully until they are absolutely dry (a couple of months) and then put them in an airtight jar with a dessicant (the little bags that come in shoe boxes and new handbags - alternatively you can use rice) and stick them in the freezer for 2 days or longer.  This kills any surviving beetles and eggs.

There are broad bean beetles (common), pea weevils and bean weevils (rarer, but happens, especially in a warm year).  Variations on the same theme, but all of them eat plant leaves and leave notches and all of them survive in seeds, unless frozen.  They eat seeds and leave holes in them.

If you don't save your own seeds, don't worry.  If you do, check them from time to time or freeze.
Title: Re: Non chemical cure for bean weevil
Post by: Robert_Brenchley on May 05, 2013, 19:32:32
A couple of years ago I had some beans in a swap which had weevil holes. You couldn't miss them when planting. I froze the seeds, then planted, and they grew perfectly happily. I think the odd weevil survived as I found one hole in another variety (self-saved seeds) when planting this year, but it really isn't a great problem.
Title: Re: Non chemical cure for bean weevil
Post by: caroline7758 on May 05, 2013, 21:15:05
That's good to know- thanks!
Title: Re: Non chemical cure for bean weevil
Post by: Digeroo on May 10, 2013, 07:48:07
I also freeze broad beans and peas fırst now.   Had some peas with holes so froze all next year and am now clear.
Title: Re: Non chemical cure for bean weevil
Post by: galina on May 10, 2013, 09:52:19
Quote from: Robert_Brenchley on May 05, 2013, 19:32:32
A couple of years ago I had some beans in a swap which had weevil holes. You couldn't miss them when planting. I froze the seeds, then planted, and they grew perfectly happily. I think the odd weevil survived as I found one hole in another variety (self-saved seeds) when planting this year, but it really isn't a great problem.

I had the same.  After freezing the whole batch, I selected the holey ones and germination tested them,  surprisingly good germination, slightly funny looking cotyledons where the holes had been.