The falling to the ground of young fruits of apples, pears etc. which occurs in June and July is known as ‘June drop’. It generally happens fairly quickly, rarely extending over a period of weeks. Insufficientat flowering time, heavy rain, drought, or sudden temperature changes are possible explanations. It is usually advisable to delay thinning until the June drop is over, except with very early apples, like Laxton’s Advance, Irish Peach, and also varieties with short stalks. Synthetic can be used to reduce June drop on some apple varieties.
Pre-harvest fruit drop comes later and is less general, being largely confined to certain varieties. For example, the fruits of Beauty of Bath are liable to drop prematurely and at one time straw was placed beneath the trees to prevent the apples bruising as they fell. Hormone sprays are now available to treat certain early varieties of apples and pears just before the fruits are ready to pick. Success depends on really thorough spraying at the right time (not less than one week and not more than three weeks before a serious drop is expected). Choose a warm day so that the diluted wash will dry quickly on the tree. It must be applied as a drenching spray on the fruit stalks, as it is there that the material acts. The effects usually persist for two to three weeks. This treatment has several advantages. Besides a decrease in the proportion of fallen apples, etc., the fruits colour better as they hang longer on the tree and the picking period for a given variety can be extended. Apple varieties which respond include Beauty of Bath, Belle de Boskoop, Ellison’s Orange, Worcester Pearmain, Annie Elizabeth, James Grieve, Laxton’s Fortune, Lord Lambourne. Some pear varieties, notably Conference (the best choice where there is room for only one pear), can be treated successfully.
In gardens where strong gales are common in September it may be worth trying aspray about a week before high winds are normally expected.