Which type of plant completes its lifecycle in one growing season?

The type of plant that completes its lifecycle in one growing season is the annual. Annual plants germinate, flower, and produce seeds all within a single season, typically dying off when the conditions become unfavorable, such as with the arrival of frost or changes in temperature. This growth cycle is typically efficient, allowing these plants to take advantage of optimal weather for a short period.

In contrast, perennials live for multiple years and typically flower and produce seeds over several seasons. Biennials have a two-year lifecycle, wherein they grow foliage in the first year and then flower and seed in the second. Evergreens, on the other hand, retain their leaves throughout the year and can be either perennial or annual depending on the specific species. Therefore, the annual plant's unique lifecycle is what distinctly classifies it as completing its lifecycle in just one growing season.