Carrot Fly do not go above 21 inches?

Hi Andrea, I'm not sure how low they fly but I remember reading that planting onions nearby deters carrot fly and (I think) carrots put off the bugs that go for onions. Do you have 22" high pots :o)

Thats what all the books say Andrea! You need to erect a barrier at least 60 cm(24") high to prevent them getting in! Good luck

I have some 'bags' which are the type you put garden waste in to take to the tip, a strong raffia type material. They are about 12 - 14" circumference and they are ideal for planting carrots. Anyone who regularly visits IKEA you will know these as the smaller recycling blue bags you can buy at the till. I am going to tie them on to the trellis area that I had erected last month, they will be up about 3-4 foot so I doubt the carrot fly will even get a sniff if they have vertigo!
Great to know that this wasn't a myth, thanks

Buzzbee that is a good idea, I will do that as well just to make sure they don't get a look in. I thought of carrying out an experiment of covering some and not others but using a garlic based spray on the fence where I'm going to erect the containers

I grew carrots for the 1st time last year. I read somewhere that if sowed thickly there wouldn't be any room for the carrot fly to get in. Keeping the root covered and the soil close to the stalks helped too I'm sure. Mine were very successfull last year and I am looking forward to planting some more this year.