Biennial plant

[1][2] In its first year, the biennial plant undergoes primary growth, during which its vegetative structures (leaves, stems, and roots) develop.

[5] Biennials do not always follow a strict two-year life cycle and the majority of plants in the wild can take 3 or more years to fully mature.

[6] Alternatively, under extreme climatic conditions, a biennial plant may complete its life cycle rapidly (e.g., in three months instead of two years).

Conversely, an annual grown under extremely favorable conditions may have highly successful seed propagation, giving it the appearance of being biennial or perennial.

Plant breeders have produced annual cultivars of several biennials that will flower the first year from seed, for example, foxglove and stock.