The response of strawberry plants in the glasshouse to foliar sprays of the growth retardant B was greatly increased by the addition of 2, 10 or 12.5 % of polyethylene glycols (‘Carbowax’) to the spray, but there was no further increase in response with 30% Carbowax. However, with all levels of Carbowax the response to B-995 under the conditions of the experiments was saturated, or nearly so, by a 2% level of the growth retardant. It is unlikely that the inherent capacity of the plant to respond to B-995 was saturated at this dosage. The circumstances suggest that although Carbowax may act by assisting uptake, the further limitation that occurred despite its use may still have been associated with uptake. Carbowax grades 200, 1500, 4000 and 6000 all were effective, although grade 200 was less so than grades 1500 and 4000. Carbowax increased the response of plants to foliar sprays of GA but not to those of CCC.