The invention relates to methods for the specific, transgenic expression of nucleic acid sequences in non-reproductive flower tissues of plants, and expression cassettes and expression vectors containing promoters which have an expression specificity for non-productive tissues of the flower. The invention also relates to organisms (preferably plants), cultures, parts, or reproduction material derived therefrom, which are transformed by means of said transgenic expression cassettes or expression vectors, and the use thereof for producing food, fodder, seeds, pharmaceuticals, or fine chemicals.