Annuals and biennials

These fast-growing, quick-flowering plants are easy to grow from seed and perfect for filling gaps in borders with short-term colour. Annuals grow, flower, set seed and die, all in the space of one year, while biennials grow in their first year and flower and set seed in their second year. There are lots of different types, including climbers, tall growing plants and others that are creeping or dwarf. Many well-known native wildflowers are annuals or biennials, such as poppies, cornflowers and foxgloves


Annuals and biennials often flower enthusiastically over a long period, from late spring to autumn. Native wildflowers create a naturalistic feel, especially among grasses, while more tender types are often bolder in form and colour and add drama to borders and containers.


Most enjoy a sunny spot and light soil that warms up quickly in spring, so they can get off to an early, fast start. They need regular watering in the early stages and during dry spells. Hardy annuals and biennials will happily germinate outdoors, while half-hardy and tender ones need extra warmth to germinate. These must be sown indoors in heat in early spring, but some types can be sown outside to flower when the temperatures have warmed sufficiently in late May.


Even hardy types tend to dislike cold, damp soil, and most won’t thrive in shade. Half-hardy and tender types can’t survive frost, so young plants should be kept indoors until late May or early June, before planting out into the garden.

Did you know?

With most annuals and biennials, you can collect the seeds at the end of their flowering season and sow the annuals the following spring and the biennials in early summer. This will give you lots of new plants for free. See our guide to sowing annuals in spring.

Growing guide

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