Annual Plants


The goal is to find care, environmental, and geographical information on annual plants in the US.

Early Findings


  • Annuals are plants that die and must be re-planted every year. They have longer bloom periods than perennials that last from early spring to the first frost.
  • Annuals are distinguished as either hardy or half-hardy. Hardy annuals can be planted directly outside, while half-hardy annuals must be started indoors.
  • Examples of hardy annuals include Larkspur, Nigella, and Calendula.
  • Examples of half-hardy annuals include Dahlias, Geraniums, and Begonias.


  • While larger annual plants are usually grown outdoors in gardens, smaller or trailing annuals can be grown inside in containers.
  • It is important to choose annuals that prefer either sun or shade based on the location they are being planted in. Different annuals have different light preferences.
  • Similarly, some annuals prefer daily moisture while other prefer drier soil.
  • Annuals that are planted before they have bloomed will typically establish faster in a garden.
  • Fertilizing is essential in growing annuals as they are considered "heavy feeders".


  • Annuals have different zones that they prefer to live in, called hardiness zones. These zones are based on a location's average annual extreme minimum temperature.
  • The zones have numbers that range from 1a to 13b, which coordinate with temperatures ranging from -51.1 C to 18.3 C.
  • For example, New York has zones including 3b, 4a, 4b, and 5a, and goes all the way up to 7b.
  • Each annual has a different hardiness zone that they can grow in. For example, the Flanders poppy is "hardy" in zones 3 through 11.

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