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Produce => Pests & Diseases => Topic started by: raisedbedted on April 16, 2009, 14:41:32

Title: Anti Carrot Fly Barrier
Post by: raisedbedted on April 16, 2009, 14:41:32
Hi everyone,

After so many years of trying to grow carrots only to have to dump many of them due to Carrot Fly I am going to try and be more prepared this year.

I am thinking of building a quadrangle approximately 8 feet square with 4 posts and 8 rails ( top and bottom) and securing fleece to the rails and corners, the height would be approx 2.5 feet.

Has anyone else done this and if so, did it work?  I have tried just covering the crop with fleece but still got the fly and also it was a nuisance to weed.
Title: Re: Anti Carrot Fly Barrier
Post by: SPUDLY on April 16, 2009, 15:05:09
Hi RBT,

It is said that the carrot fly dont travel higher than about 50 to 60cm, so a barrier 2.5' high should do the trick, although i have not had the pleasure of this pest yet.
Title: Re: Anti Carrot Fly Barrier
Post by: raisedbedted on April 16, 2009, 15:14:49
Thanks, I'll send some over  ;D

The RHS web site suggest using polythene for the sides but I'm aiming for fleece as I have some in the right size and I think polythene would give too much resisitance and so would need firmer anchoring.

Title: Re: Anti Carrot Fly Barrier
Post by: Tee Gee on April 16, 2009, 15:22:36
QuoteIt is said that the carrot fly dont travel higher than about 50 to 60cm,

I agree with the theory Spudly but in practice I find it quite a different situation.

I have thought long and hard over the years and my conclusion is; in lab or windless situation the 50cm might be OK but given a wind or thermal currents the fly is often wafted over the barrier.

Although I haven't witnessed this happening, what I have seen; is how dandelion clocks/seed float on a windless day...........they fly in an undulating fashion presumably on thermal currents and I think you have all noticed how dandelion plants seem to spring up everywhere backing up  my theory of how carrot fly get over a barrier.
Title: Re: Anti Carrot Fly Barrier
Post by: davyw1 on April 16, 2009, 15:25:08
if it only fly,s 50 to 60cm how does it get over my 4ft garden fence,  Yes i shut the gate.
Title: Re: Anti Carrot Fly Barrier
Post by: Barnowl on April 16, 2009, 17:08:18
Roof with fine enviromesh?
Title: Re: Anti Carrot Fly Barrier
Post by: shirlton on April 16, 2009, 17:22:46
Fleece is ok as long as it stays in one piece but very often it gets ripped in the wind. I have grown them under fleece and also enviromesh. Anything that keeps the dratted fly out will do. I think someone on here said the Ikea plain net curtains were quite cheap. I had thought of trying that. Would certainly be cheaper than enviromesh but wether or not it would tear, I don't know
Title: Re: Anti Carrot Fly Barrier
Post by: raisedbedted on April 17, 2009, 16:17:20
I think if I'm going to roof then I may as well just lay the enviromesh over the top of the carrots with some little hoops to take some of the weight, have a lot of the v fine enviromesh so I'll try that - trouble is normally thye still get in - probbaly when I am weeding.
Title: Re: Anti Carrot Fly Barrier
Post by: Tee Gee on April 17, 2009, 16:42:36
This is how I sometimes cover mine;

(http://www.thegardenersalmanac.co.uk/Data/Carrot%20fly/Carrot%20fly%20protection.jpg)

The gap has been left on purpose to show the carrots underneath. In practice this part would be weighted down.
Title: Re: Anti Carrot Fly Barrier
Post by: Squashman on April 17, 2009, 19:15:14
I grow mine in a cold frame constructed of old patio doors with a roof made from "Wondermesh". I have 5 rows sown, the first of which should be ready when I dig my first early potatoes.
The wondermesh cost me .24p per square metre. I have used Enviromesh for the last few years for cabbages etc, and well pleased with the result, but second hand wondermesh is by far cheaper.
Title: Re: Anti Carrot Fly Barrier
Post by: realfood on April 17, 2009, 19:40:33
I use the Lidl equivalent of environmesh £5 for 5m x 2 m I think. For photo see  my carrot page http://www.growyourown.info/page95.html
I use some old timber to make sure that the edges are kept in contact with the ground.
I lifted the last of my carrots about a month ago. No carrot fly.
Title: Re: Anti Carrot Fly Barrier
Post by: shirlton on April 18, 2009, 10:35:23
Is it enviromesh or fleece. Looked at the pic and it looks like fleece
Title: Re: Anti Carrot Fly Barrier
Post by: shirlton on April 20, 2009, 19:22:09
These are the wire mesh frames that Tone made last year. We bought one o them staple guns and have fixed fleece inside to stop both the fox and the fly. The ends are fom the Keter GH that got blown down
Title: Re: Anti Carrot Fly Barrier
Post by: laurieuk on April 20, 2009, 20:06:16
I am not sure if I will be liked for saying this but some years ago I was thinking of using a barrier and attended a talk by an RHS veg man . I wanted to know details of the life cycle of the carrot fly. It overwinters in the soil so if you had any trace of carrot in that area that you protected you could fence him IN when you are trying to keep him out. You do need to keep a careful check on where you have previously had your carrot crop. I know you cannot grow a huge crop in containers but the ones on my website never get carrot fly as they are too high.
Title: Re: Anti Carrot Fly Barrier
Post by: Tee Gee on April 20, 2009, 20:20:37
I agree Laurie!

This link gives an insight to the carrot fly life cycle for those that are interested in what Laurie was advised; http://www.thegardenersalmanac.co.uk/Data/Carrot%20fly/Carrot%20fly.htm (http://www.thegardenersalmanac.co.uk/Data/Carrot%20fly/Carrot%20fly.htm)
Title: Re: Anti Carrot Fly Barrier
Post by: thifasmom on April 20, 2009, 21:35:21
Quote from: shirlton on April 20, 2009, 19:22:09
These are the wire mesh frames that Tone made last year. We bought one o them staple guns and have fixed fleece inside to stop both the fox and the fly. The ends are fom the Keter GH that got blown down

your Tone builds such lovely neat looking structures, my Tony is very good with his hands practically rebuilt our home but when i want him to build me anything for the garden he just does any old slapdash thing or tells me my idea cant be built ::) (liar). so i normally muddle along and try and do it myself but most of my structures only last the season :-\ and have to be built again the following year :(.
Title: Re: Anti Carrot Fly Barrier
Post by: shirlton on April 21, 2009, 08:52:34
Hi Laurie , We rotate our crops so as not to build up the pests. I have grown carrots under fleece every year and never had carrot fly yet. The point of the pic was to show how a wire cage had been adapted to keep the fly out. We have to use the cages to keep the foxes out.These are some of the carrots we grew