As our seedling parsnips and carrots appear, don’t neglect to thin them out. It almost seems wrong after they finally pop up to start killing some off, but if we don’t give them enough space we end up with a tiny inedible crop, which is not what we want. Be hard and ruthless, force yourself!
With your carrots, thin in the evening as there are less of the dreaded carrot flies about to be attracted to the scent of the bruised foliage. If carrot fly is a particular problem to you, horticultural fleece makes a good barrier and you can grow resistant varieties like “Flyaway”.
Resistance lies in them having low levels of chlorogenic acid, a chemical that the larvae of the carrot fly need for survival. This means that they appear to be unattractive to the fly and even if your crop is attacked to some degree the larvae will soon die after doing relatively little damage.