Fruit split is a disfiguring condition where one or more splits, often branched, are seen on the surface of apples, pears and other fruit. The splits are usually not very deep, but they cause wounds that allow diseases and pests to attack otherwise healthy (and tasty) fruit. Even if the fruit remains healthy the splits are disfiguring leaving the fruit only good for juicing or cooking.
Fruit split is a condition, not a disease, as it is caused by an irregular supply of water. The splits usually occur when rain follows a protracted dry spell and the sudden availability of moisture causes the fruit to swell too quickly.
The remedy is easier said than done as it is simply to ensure your fruit trees have a steady supply of water. Given varying weather conditions this is not as straightforward as might appear and of course, hosepipe bans can spoil the best laid plans.
The real solution therefore is a longer term one. It begins when you plant fruit trees, when it is important to incorporate plenty of well rotted organic matter in the planting mix. Good compost helps the soil retain moisture and so increases its ability to release water to plant roots in dry spells. Thereafter, you can continue to improve those moisture retaining properties by mulching. Ideally you should use more well rotted manure or garden compost, but failing that fresh grass clippings laid 2ins (5cms) deep will help retain moisture and will eventually rot down and improve the soil. Apply this mulch in the spring, when the soil is wet.