How Do I Know When My Plums Are Ready to Pick?

Timing the plum harvest correctly is one of the most important skills in stone fruit growing. Pick too early and the fruit is hard, acidic and lacking sugar. Leave it too long and it becomes overripe, falls, attracts wasps and deteriorates rapidly. Fortunately, ripe plums give clear signals if you know what to look for — and developing a feel for them means you will never miss the best window again.

Variety ripening times

Different plum varieties ripen at very different times. Early varieties such as 'Early Laxton' and 'Opal' are ready in late July. Midseason varieties including 'Victoria' — the most widely grown — ripen from mid-August. Late varieties such as 'Marjorie's Seedling' and 'Czar' can be ready from late August through to October. Knowing your variety's expected ripening window removes much of the guesswork. In a warm summer, ripening can be a week or two earlier than average; in a cold season, later.

Colour as an indicator

Colour change is the most visible indicator but should not be used alone. Purple varieties become progressively deeper purple-blue as they ripen, with a dusty bloom developing on the skin surface. Yellow and green varieties develop a yellow flush or soften slightly in colour. However, colour is variety-dependent and can reach its final hue while the fruit is still unripe inside. Use colour as a cue to begin checking more carefully, not as the sole harvest trigger.

The feel test

Gently squeeze the shoulder of the plum (the area around the stalk end) — a ripe plum gives slightly under pressure but has not lost its structure. An underripe plum is rock hard. An overripe plum is very soft and the flesh separates from the stone when cut. Feel the fruit on the tree every day or two as the harvest window approaches — the transition from firm-ripe to soft can happen quickly in warm weather.

Tasting individual fruits

Taste a fruit from the tree as the season progresses — there is no substitute for this. A fully ripe dessert plum has a rich sweetness with a balance of acidity, and the flesh comes cleanly away from the stone. If the flesh clings to the stone and tastes sharp, leave the crop for a few more days.

Harvesting in stages

Plums on a tree do not all ripen simultaneously. Fruits in full sun ripens ahead of those in shade; fruits at the top of the tree often lead lower ones by several days. Check and pick in stages over one to three weeks rather than stripping the whole tree at once.