Crab apple (Malus sylvestris) is a small, attractive deciduous tree which produces white/pink blossom in the spring followed by crops of apples in the autumn. The flowers are hermaphrodite and are pollinated by insects; they are also good pollinizers in apple orchards. It can take five years or more for the tree to be mature enough to flower and fruit.
Crab apple fruits are very small and normally green, ripening to yellow or red. They are less than 3.5cm in diameter and have a long stalk. It is by the fruit that you can best identify a crab apple - they are almost like cherries in shape and size.
Crab apples are an excellent source of pectin but are very sour to the taste. Their juice can be made into a ruby-coloured preserve with a full, spicy flavour. The flesh is suitable for making jams, jellies and preserves.