Why Are My Apricots Small and Underdeveloped?

Small apricots are frustrating because they suggest the tree is producing fruit but not fulfilling its potential. In most cases, the tree is carrying too many fruits for its resources, is not receiving enough water during the critical fruit development period, or lacks the potassium needed to support good fruit size and sweetness. All three problems are correctable with management changes during the current season.

Too many fruits (over-cropping)

An apricot tree sets far more fruit than it can develop to full size. Without thinning, the tree distributes its resources among many fruits and produces a large number of small, flavourless apricots rather than a moderate number of large, richly flavoured ones. Thin fruitlets to a spacing of 8–10 cm along the branch after the natural June drop is complete. This feels counterintuitive but consistently produces larger fruit — often double the size compared to unthinned fruit from the same tree.

Water stress during cell division

Fruit size is largely determined during the cell-division phase immediately after pollination — the first three to four weeks after fruit set. Water stress during this phase limits cell division and permanently reduces the maximum size the fruit can reach. Even if watering is improved later in the season, the cell deficit cannot be recovered. Water consistently and generously from fruit set through to harvest. Mulch the root zone to retain soil moisture.

Potassium deficiency

Potassium is essential for fruit size and sweetness. Trees growing in sandy or heavily leached soils, or wall-trained trees in containers, are particularly vulnerable to potassium deficiency. Symptoms include small, poorly flavoured fruit with some leaf edge scorch. Apply sulphate of potash in February and again in June. Tomato fertilisers (high in potassium) can be used as a summer liquid feed for wall-trained trees.

Variety

Some apricot varieties are naturally smaller-fruited than others. If all management practices are correct and fruit is still consistently small, the variety may simply be a small-fruited type. Modern varieties such as Flavorcot and Goldcot consistently produce larger fruit than older or unnamed varieties grown from stone.