Why Are My Apricots Developing Mould After Picking?

Freshly picked apricots that develop visible mould within one or two days of harvest have almost certainly been infected before they were picked. There are two main post-harvest moulds on apricots: brown rot (Monilinia laxa), which produces the same cream-spored, rapidly spreading brown decay seen on the tree, and grey mould (Botrytis cinerea), which produces a grey-brown fuzzy growth. Both signal that management of the tree during the growing season needs attention to reduce pre-harvest infection levels.

Brown rot after harvest

When brown rot appears within 24–48 hours of picking, the fruit was already infected before harvest — the infection was latent inside the fruit before visible symptoms appeared. This occurs when Monilinia infection levels on the tree are high due to mummified fruit left from previous seasons, wet weather during ripening, or fruit cracking providing entry wounds. Reduce next year's brown rot burden by: removing all mummified fruit in winter; applying copper fungicide at blossom; and harvesting fruit before it is fully ripe in wet seasons.

Grey mould (Botrytis)

Grey mould infects ripe or damaged fruit rapidly in cool, humid conditions — particularly in a damp harvest basket or tray with poor air circulation. Unlike brown rot, grey mould is more often a post-harvest problem than a pre-harvest one. Keep harvested fruit in shallow, ventilated trays. Never cover harvested apricots with plastic film or place them in sealed bags. Inspect the storage container daily and remove any fruit showing early signs of mould — a single infected fruit spreads spores to all adjacent fruit within hours.

Spreading between stored fruit

Once one fruit shows mould, adjacent fruit are at high risk of infection through direct contact. Store fruit in a single layer where possible — certainly no more than two layers — and ensure no fruit is touching a mouldy neighbour. Check daily during the storage period and remove any deteriorating fruit immediately.

Using excess fruit quickly

In years when a large crop matures rapidly in warm weather, harvest the whole crop promptly and process any surplus within a day or two — jam, compote, or freezing whole. Do not leave fruit on the tree beyond peak ripeness hoping to extend the season; overripe fruit is far more susceptible to all post-harvest moulds.