Common Soft Fruit Pests

For many gardeners, growing their own fruit can be one of the high-points of the gardening year – but there’s a whole host of insects and other pests that find your prized soft fruit every bit as tasty as you do.

Keeping produce in top condition and free from pests, mildews and disease calls for high levels of vigilance if you want to be able to put fruit to be proud of on your table.

Capsid Bugs

These small, sap-sucking pests attack a wide range of garden plants but amongst the soft fruits, gooseberries and currants seem to be the most prone to damage. They puncture the leaf surface, being especially fond of young leaves and inject saliva into the plant as they feed. This kills off the cells immediately around the puncture site, leading to the appearance of a series of characteristic brown spots. As the leaves expand and grow, the dead areas rip, leaving behind a lead covered in a series of ragged, brown-edged tears.

There’s no treatment for the damage itself, but if you inspect your plants from late spring onwards and spray with insecticidal soap or bifenthrin if there are any signs of the pests themselves or damage to be seen, you should be able to prevent things getting out of hand.

Fruit Flies

The adult fruit fly is a small (3mm) yellow/brown fly, usually with a striped abdomen and red eyes, and is a common nuisance in home and gardens – though they don’t bite. They are attracted to fruit – especially if it’s damaged – alcohol and sweet drinks, making them annoying pests during any outdoor eating in the summer months.

In ideal conditions, their life cycle goes from egg to adult in under a fortnight – so they can build up to fairly large numbers surprisingly quickly.

Ordinary fly sprays are effective against the fruit fly, and residual insecticides work well against the larvae, if you can discover where they are breeding.

Raspberry Beetles

These insects are probably the single most serious pest of raspberries – also affecting blackberries, loganberries, tayberries and other forms of hybrid cane soft fruits.

The adults eat the plant’s flowers while larvae bore into the fruits themselves and eat them from the inside, causing them to dry up at the stalk and turn a greyish/brown colour.

The brown 5mm-long adults lay their eggs on the flowers in late spring and early summer; when the young hatch they start feeding at the stalk end of the fruit as it develops, moving inside later where they eventually grow to around 8mm in length. Later in the summer they move into the soil, pupate and overwinter before emerging as adults the following year.

Controlling these pests involves catching the larvae before they burrow inside and spraying or dusting with a good contact insecticide – the timing of the treatment depending on the type of fruit affected. Raspberries should be treated when the first pink fruits are seen, blackberries when the first flowers are opening and loganberries, tayberries and the like need to be dusted as soon as most of the petals have fallen.

Mildew

A wide range of soft fruits are prone to mildews of one kind or another with strawberries, vines and gooseberries being particularly likely to suffer from this problem. In all cases the symptoms are usually depressingly similar, involving grey mouldy patches spreading across the leaves, wilting, leaf loss and dull, shrivelled or split fruits.

Control involves swift action once the problem has been spotted – starting with a vigorous pruning out of any infected areas and then burning the prunings along with any fallen leaves or other diseased material.

The next stage involves treating the plant with fungicide. A wide range of proprietary brands are available, but it is important to read the label very carefully since not all products are authorised for use on every kind of plant. Vines, for instance, can only be treated with sulphur dust, while for some kinds of fruit – including gooseberries – you can also use myclobutanil concentrate.

There’s nothing quite like enjoying your own fruit – and if you keep a careful watch on yours as it grows, you should be able to make sure that you’re not sharing it with a whole army of unwanted guests!