A method for the separation of gibberellins from mixtures thereof by selective silylation or desilylation, as well as substantially pure gibberellins prepared thereby. For example, to a solution of a mixture of GA4 and GA7 in DMF was added imidazole. After imidazole was completely dissolved, butyldimethylsilyl chloride was added. After two days of stirring, acetic acid was added which precipitated a white solid (silyl ether of GA7). After filtration GA4 was recovered from the filtrate. Desilylation of the silyl ether of GA7 yielded GA7.