Abstract A method is described of inducing polyploids in detached stolons using an aqueous solution of colchicine, DMSO and glycerol. The donor plant remains uncontaminated and can be grown further to produce more stolons. The putative colchiploids can be chosen on a morphological basis and confirmed cytologically. About 10% of the treated stolons, starting with diploid and tetraploid strawberry, are converted, but 50% nonviability is caused by the treatment. The method can be applied to some other species and shoot types, using other chemicals with chromosome doubling or reducing effect, or even mutagens. The principle can be used without colchicine treatment to obtain strawberry plants from stolons without contamination of the soil around the main clone.