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how can I avoid carrot fly on my allotment (6 replies)

8 years ago
Oldchap 8 years ago

I've grown carrots for a few years now and carrot fly is a real problem on the allotment. I've been using fleece for the last few seasons, but last summer the little critters (not what they're called when the carrots are lifted 🙂 ) still managed to attack the roots.

I rotate the crops every season, but was wondering if anyone has any tips that work?



Saving Ryan's Privet

8 years ago
Florexpert 8 years ago

Hi Oldchap,

You could try growing your carrots in barrels or (very) raised beds over 60 cm high, as the carrot flies tend to fly very near ground level.

As a second prevention step, avoid thinning out seedlings at all costs! When you pull out unwanted seedlings, it bruise the roots and releases the chemical the dreaded fly can smell and detect, even from far away. So it's a good idea to sow you carrots with the correct spacing straight away and leave them untouched until harvest.

You can sow thinly by either mixing the carrot seeds with sand, or with radish seeds, which will germinate & grow and be harvested way before the carrots!

You can also sow either very early or late rather than the traditional mid spring, which is carrot fly season at its peak!

Then don't leave any carrots around overwinter, as it produces the next generation of carrot flies!

All this also applies to parsnips, which carrot flies equally love...

If everything fails, try the carrot variety 'Flyaway'! 🙂

8 years ago
Oldchap 8 years ago

thanks florexpert

Saving Ryan's Privet

old git
8 years ago
old git 8 years ago

Great advice from Florexpert there is also the method using horticultural fleece or a fine micro mesh as a barrier to keep the fly off the plants, of course rotation is important here as if there are any carrot fly pupae overwintering they may hatch out within the barrier and think they are in carrot fly heaven . Thing is though on a personal basis I have never had any success with the carrot fly resistant varieties they have been no better or worse than the Autunum King types.Since the banning of chemicals such as Bromophos I have lately given up with carrots but this year with the help of raised beds and some mesh I will give them another try.It does however bug me a little that farmers can be trusted to throw chemicals all over the place but we irresponsible gardeners are not. There is not a trace of carrot fly damage on supermarket carrots so perhaps it is time that gardeners are allowed to poison themselves if they so wish.This year it is raised beds after many years of veg gardening on the flat.

8 years ago
Ednaduck 8 years ago


As well as the other advice try these ideas too.I plant onions or garlic along side my carrots and that seems to help as the flies don't like the smell.  I also use carrot seeds tapes which help avoid the thinning out process as they are already well spaced. Good luck

8 years ago
poppy 8 years ago

marigolds planted next to them are good an my dad alway as soon as they started to come up walked down the line right over them as he said that stopped the fly getting in to so its some thing we always do now too

2 years ago
big89 2 years ago

You can sow thinly by either mixing the carrot seeds with sand

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