The Difference Between Annual, Biennial and Perennial Plants
Know the difference between flower types to achieve your gardening goals.
Annual flowers complete their lifecycle from seed to death in one growing season. Some plants grown as annuals in cold climates are actually perennials in milder locations.
Tender annuals like impatiens and coleus are sensitive to frost. Half-hardy annuals like ageratum and lobelia can tolerate cool air and soil, but can be damaged by frost. Hardy annuals like alyssum and pansies tolerate cold soil, cold air and frost. Adjust planting times based on this.
True perennials hardy to your location live for multiple years in the garden.
A bit more information: Some growers and gardeners start biennials indoors early. The early start encourages biennial plants to bloom and die the first year in the garden.