Many thanks for your recent enquiry regarding the carrot fly prevention measures you currently have in place. Carrot fly is a perpetual pest in the world of carrot growing, and placing a fine mesh barrier around is a common – and very effective – way of preventing the low-flying adult flies from landing in the bed and laying eggs. The mesh fence does not need a roof to cover the crop and as long as the bed is enclosed by a 60cm high screen, the adults should not be able to enter. You are probably safe to remove any perimeter blockade you have in place now as the last generation of adult flies emerges in September. It’s also important in any veg growing situation – but especially when carrots are involved – to practice crop rotation, and ensure you don’t grow the same plants, or related crops, on the same site for at least three years. Larvae and pupae overwinter in the soil and will make short work of your 2009 carrot crop if not!
You may be interested to learn we are introducing a custom-made carrot fly screen to our 2009 range which consists of 8m of fine mesh netting, aluminium stakes and clips – it should retail at £29.95, carries the product code of GDN-448 and can be viewed on our website at the end of December.
Hopefully this information is of help and good luck with your carrot-growing exploits next year!