There's nothing more frustrating than going to lift your long-awaited carrot crop to find that half of the roots have split open. Here are some tips as to why it happens and how you can avoid it recurring.
Carrots
and parsnips are nearly drought proof on good soils,
but like beetroot, radish, and other root crops they can develop
split roots when they receive irregular moisture levels. Summer
thunderstorms after long periods of drought can cause the
root to take up a sudden increased volume of water. The root
then splits open as the skin cannot cope with the sudden surge
in growth. This can lead to secondary infections such as bacterial
soft rots making the roots virtually inedible.
Free-draining soils such as sand or chalk can pose the greatest challenge, and so the addition of plenty of well-rotted organic matter to increase the soil's moisture retentiveness can help deter the problem, as can increasing crop spacings. Regular watering is also essential where soils are not very moisture retentive to ensure a steady growth rate.
Give the rows a thorough soaking every two weeks initially, rising to every week as the roots near their harvest stage (allowing for rainfall).
By ensuring that the plants never fall short of water, you should be lifting perfect roots for the rest of the season.