Biennial plants are plants that require two growing seasons to fill their life cycle. The first season from seed, they will make leaf growth; they will then overwinter and flower in the following year then die.
Some of the better known biennials are Sweet Williams (Dianthus barbatus), Foxgloves ( Digitalis purpurea) and Canterbury bells ( Campanula medium).
Some perennial plants are called biennials because they flower, not in the first year that they are sown, but in the second.
Examples of these are Delphiniums.
© copyright 1999, P. A. Owen