Why Are My Cherries Falling Off Before They Ripen?

Premature fruit drop — cherries that fall from the tree while still small, green, or only partly coloured — is one of the most disheartening problems a cherry grower encounters. You can see a potential crop forming, and then it disappears before harvest. Several different problems can cause this, and the stage at which the fruit drops provides an important clue to the cause.

Incomplete pollination — small fruit drops shortly after flowering

When fertilisation is incomplete because compatible pollen was not transferred effectively — due to wet weather during flowering, cold temperatures reducing bee activity, or a missing pollinator variety — the developing fruitlets are quickly aborted. The tree sheds these tiny, hard, pea-sized fruits within two to three weeks of petal fall. If most of the fruit on the tree drops at this stage, pollination was the problem. For next season, ensure a compatible pollinator variety is within range and consider hand-pollinating with a soft brush on dry, mild days during peak flowering.

June drop — natural self-thinning

Cherry trees, like apples, perform a natural self-thinning in early summer, typically in May to June in temperate climates. The tree drops a proportion of its fruit when it assesses that it cannot ripen the full set given current conditions. A moderate drop at this stage is normal and actually beneficial — it concentrates resources on the remaining fruit, which will develop larger. Only intervene if the drop is excessive and no fruit remains on the tree.

Drought and irregular watering

Drought stress during the fruit development period causes the tree to shed fruit to reduce its resource demands. Cherries are particularly sensitive to moisture stress in the four to six weeks after petal fall, when the fruit is swelling rapidly. Maintain a consistent soil moisture level by deep watering during dry spells and by keeping a thick mulch around the root zone. Avoid allowing the soil to dry out completely and then watering heavily — this sudden change in moisture levels also triggers drop.

Brown rot and fungal infection

Brown rot (Monilinia spp.) and other fungal infections can cause individual cherries to rot and fall prematurely. Infected fruit usually shows a brown discolouration spreading from the skin inward, sometimes with white fungal spore pustules. Remove all affected fruit promptly, including any mummified fruit left from previous seasons, and consider a copper fungicide application before flowering and again after petal fall in orchards with a history of the disease.