What do we call a plant that lives for more than two years?

A plant that lives for more than two years is referred to as a perennial. Perennials are characterized by their ability to survive through multiple growing seasons, often re-emerging after winter or dormancy. They may die back to the ground in colder months but will regrow each spring from their rootstock or crown. This resilience allows them to thrive in various environments and be a stable part of gardens or landscapes over time.

In contrast, annual plants complete their life cycle within a single growing season, germinating, flowering, and dying all within one year. Biennials take two years to complete their life cycle, typically growing foliage in the first year and flowering in the second. The term "seasonal" generally refers to plants that may have specific growth periods or characteristics associated with particular seasons, but it does not define longevity in the same way that perennial does. Thus, the definition of a perennial is clear and distinct in horticulture, making it the correct answer in this context.