Rod wrote:
On 12 Feb, 10:12, Chris ] wrote:
Last year our carrots were ruined by carrot root fly.

It was probably my fault - because I had been adding discarded
root-fly-infested bits of carrot to the compost heap - so that probably
went back into the earth.

Anyway - I want to do better this year.
Someone on Gardeners Question Time recommended growing carrots under
fleece for the whole of their lives.

The enviromesh covered cages in this picture are my solution, that was
taken in spring last year. We are still eating undamaged carrots from
the cage nearest to the camera. As an added benefit, any unused space
in there is now covered by a ground cover mat and my overwintered
flower and veg seedlings and first sowing of peas in pvc guttering are
sitting in there.
http://myweb.tiscali.co.uk/rodsgarden/Rod's%20plot01/images/image0001.jpg
A problem I find with fleece and eviromesh is that most simple ways of
using them end with the fabric damaged making re-use difficult. I
expect these cages to last for several years.
I also suffer from this bug (add g e r)I have yet to find a complete
solution. I have tried enviromesh, no fly but poor carrot crop. another
solution is, as already posted, plant alternatively with onions. As we
use a lot of pickling onions that works quite well, but does not
completely irradicate them. My best crop were grown in Builders
merchants 1 ton bags, a bout half filled with soil, so that there is
quite a bit of bag surrounding the sowings. Works well but is a lot of
work. How do professional growers manage?