SummaryThe application of GA3 alone or in combination with auxins and/or diphenylurea delayed the development of red colour on cherries if applied at the cot-split stage or two weeks after full bloom. Petal-fall applications were less effective and blossom-time applications ineffective in this respect. The hormone mixtures did not induce a significantly different response from GA3 alone. Application of daminozide enhanced red colour development, totally counteracting the effect of GA3 applied at petal-fall and partially that of GA3 applied later .The soluble solids content of the fruits was reduced by the hormones and increased by daminozide. Fruits were smaller where hormone treatment had greatly increased yield but were larger where they only doubled the yield. Daminozide increased fruit size. Hormones affected fruit mineral contents, P, K and B being reduced in the flesh and N, P and K in the stones. Stone mineral levels were much higher than those in the flesh, particularly Ca.