Diagnose by symptom
Deformed or maggoty fruit
Cracked, deformed fruit, dark spots or grubs inside — fruit diseases and pests:
Diseases
Apple scab
Olive-green, velvety, blurred spots appear on the leaves and gradually darken and turn brown; heavily infected leaves tu…
DiseasePlum pox (Sharka)
The disease attacks plum, apricot and peach, along with other species of the genus Prunus. Pale, chlorotic rings, spots …
DiseaseBrown rot (Monilinia)
On pome and stone fruit, brown, enlarging rot spots appear, on which concentrically arranged, grey-beige cushions of spo…
Pests
Frequently asked questions
Why are my fruits deformed and misshapen?
Deformed fruits most often result from poor pollination (uneven development), pest feeding on flowers and young fruitlets, and diseases. Nutrient deficiencies (e.g. calcium), water stress during fruit set, and frost damage to blossoms can also be to blame. To narrow the cause, check whether the deformity is present from the fruitlet stage or only appears as the fruit grows.
Does poor pollination deform fruit?
Yes – when pollination is incomplete, some ovules fail to develop, so the fruit grows unevenly and turns lopsided or one-sided (typical in strawberries, apples, squash). Cool, rainy weather during flowering, which limits bee flight, encourages this. Planting pollinator varieties and insect-attracting plants helps.
Can pests cause fruit deformation?
Yes – pests that pierce or feed on blossoms and young fruitlets (e.g. apple blossom weevil, capsid bugs, thrips) damage the tissue, so the fruit grows crooked, corky or russeted. Larvae inside the fruit (codling moth) also disrupt its development. Early inspections and protection during flowering limit such damage.