I've been surprised to hear from many people that they have struggled to grow good quality carrots - it's the first vegetable I grew, and I never fail to get a great crop!  Enough gloating - here are my tips:

1) Sow the seed in rows about 6” apart, guided by a piece of string or plank of wood. I don’t actually measure anything – where’s the fun in that; just estimate and see what happens from year to year.

2) Every week, lift the mesh covering (see below) and remove any weeds that appear between the rows.

3) Don’t bother ‘thinning’ the carrots. The seedlings will find their own space and any that don’t make it... well, that’s the survival of the fittest in action.

4) Cover the crop in enviromesh or another very fine mesh. Use unfolded paperclips to pin it down fairly tightly so that there aren’t any large gaps along the bottoms for pesky carrot fly to get in. No matter what you read about carrot fly lifecycles, keep the mesh on from the moment the seeds are sown until you lift the very last carrot.

5) If the ‘crowns’ of the carrots – the bit beneath the green tops – shows through the soil, sprinkle some soil, compost or sand along the tops. This stops them from going green, and improves the soil for the next season.

6) Only water the carrots if you can be bothered. If you water, you may get larger carrots, but they will grow regardless, so don’t give yourself extra work.

About 2 months after sowing, push your finger into the soil, near to one of the carrot tops. Have a poke around, and if you’ve done the above, you should find some tasty young carrots.