Tulip bulbs, cv. Apeldoorn, that had been stored at 5 deg C for 12 or 18 weeks before planting on 9 November, 15 December or 17 January were forced at 15 or 19 deg under continuous light, and chlormequat at 0-16 g/pot was applied to the soil when the shoots were about 3 cm above the soil. The number of days to flowering and the flowering duration were not affected by chlormequat, but stem length at flowering time and finally, and the lengths of the lowest and highest internodes and of the perianth were all reduced in proportion to the amount applied. Later planting shortened the period to flowering as well as stem length, and forcing at 19 deg had similar effects when compared with 15 deg . Storage for 18 weeks also shortened the period to flowering, but stem lengths were longer than those in bulbs stored for 12 weeks; in addition, the effect of chlormequat on the length of the highest internode was enhanced. The response to the various treatments in terms of length of the different organs was in the order forcing temperature > chlormequat > planting date > storage period. (Abstract retrieved from CAB Abstracts by CABI’s permission)