Ideally, once a carrot is larger than one inch and fairly wide, you can start harvesting carrots without too many problems. These smaller carrots will not store, so you must eat them right away. By thinning them out a little bit you will be able to grow larger carrots.
Main crop carrots are ready to harvest when they are five or more inches long and orange.
Basically... do they look like a carrot you’d buy in the shop? If yes, you are ready to harvest.
How to harvest carrots
Obviously when harvesting carrots you need to be careful of breaking the root, and also careful of the smell that carrots give off when they are harvested. So, ideally, you want to gently raise them with a fork, a few inches away from the stem of the plant.
Let’s face it, that sounds easy to do but isn’t all that easy... because there are often a lot of carrots in the ground. Just be as careful as you can.
Now, the tradition says that carrot root fly can smell the carrots you are harvesting from miles away... and so you should harvest when it is raining, or when it has just stopped. Really, I don’t know if that is true or not. People also used to plant things like thyme, cotton lavender, marigolds or nasturtium around carrot borders to prevent the smell of carrots attracting the fly...
No idea if it works. I suspect it doesn’t, but it probably makes your vegetable garden look prettier.
Should you store carrots?
Originally the reason carrots were so popular were they could be stored in a clamp for many many months. And, if you want to store them that is still the best way... in theory... although it takes a great deal of effort.
Carrots will last weeks in a pantry or other cool space, although the fresher they are the better they taste.
Until the first frosts come the best places to store them is often the ground, but keep an eye out on the crop for any signs of them going over, such as brown leaves. And of course, you will probably want to keep a weather eye out for pests, damage and so on that can wipe out your crop if you leave them out too long.
Modern methods are probably the best if you want to store them long term... you can clean them, blanch them, and freeze them. Lots of people eat carrots frozen anyway. It won’t taste as good as newly pulled carrot, but on the other hand you will be eating your own carrot during the depths of winter.