I have tried a new method this year, I rarely grow because of the issues and hassle however...
This year I have grown New Market and I have used a spray, yep orange peel, mint and garlic, spray the plants once a week.
So did it work?
Yep, from a complete row (20ft) only two had fly, no netting or other methods, just simply spraying once a week.
I have also sown 4 more rows (another experiment) of the same carrot to see if I can get a winter crop as the packet and other info suggests you can sow upto August, all being well plenty of carrots for winter.