Annuals are plants that bloom in the same year that they are planted. A hardy annual is an annual plant that can tolerate frost and its seeds can tolerate a cold winter.
The seeds of hardy annuals can be sown in the open garden in early spring or autumn. The seeds of hardy annuals can germinate in cold soil and the seedlings and mature plants can withstand frost.
The seeds of hardy annuals also can winter over outdoors and germinate the following spring. (There are hardy, half-hardy, and tender annuals. Tender annuals are plants that are easily killed by a light frost and their seeds can not survive outdoors through winter. Half-hardy annuals can withstand light frost, but their seed can not overwinter outdoors in cold regions.)
Hardy annuals can withstand frosts in autumn and winter as well as spring. They can be started in late summer or early fall and will grow until killed by a hard freeze. A hard freeze is several hours of temperatures at 28°F (-2.2°C) or colder.
Hardy annuals are a good choice for early spring and late summer and early autumn planting. They do not grow well in the warm time of the year; most hardy annuals will bolt and set seed when temperatures climb into the 80°sF (26°sC).
Grow hardy annuals in late winter and early spring. Grow tender annuals in summer. Grow hardy annuals again in autumn and winter.
|A-G Common Name
|F-P Common Name
|Flowering cabbage and kale
|Digitalis purpurea ‘Foxy’
|Viola x wittrockiana
|R-Z Common Name
|Rose of heaven
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