Hardy annuals are wonderful colorful plants for providing a summer-long display. Some kinds can also be sown during the fall with a view to providing late spring and early summer blossoms as well, especially in warmer districts. However, there are insufficient different varieties available that will respond to this method of cultivation to enable a border solely of early flowering annuals to be created in cooler parts of the country.

In cool winter areas fall-sown annuals are more usually grown to create highlights in the mixed border. However, it is generally conceded that in most gardens spring sown annuals are the only option available to the gardener, especially where the soil freezes solid during the winter and there is heavy snowfall. Few over-wintering annual flowers can endure such conditions.

Not that this is much of an impediment, for most gardeners agree that an annual that is raised from seed that grows on unchecked into the summer is likely to make a better plant, even if later flowering, than one that has over-wintered, even under mild conditions.

An annual border should be sown on soil that is crumbly and will rake out into a fine tilth. In order to achieve suitable soil conditions preparations should be made well before sowing. When spring sowing is proposed turn the soil over in as large lumps as possible during the fall and winter and allow it to weather. It will then break down into a crumbly tilth in the spring that is perfect to receive the seeds.

For most annuals the incorporation of well-rotted garden compost or manure into the soil is beneficial when digging, as it will then have time to decompose properly before the seeds are sown. However, leave it out of any areas where plants like nasturtiums might be expected to grow. These much prefer a lean hungry soil. A rich soil promotes lush leafy growth at the expense of flowers.

With the soil raked and leveled, shuffle across it with the feet from side to side. This creates a firm seed bed and does not compact the soil and make root penetration difficult. Rake the soil gently to level it and then mark out the areas designated to each annual with a trail of sand. Make bold groups rather than intricate patterns, generally arranging the taller varieties to the back of the border.

When sowing the seeds, rather than broadcasting or scattering them over each designated area as is traditional, create short drills at the distance apart at which the plants should eventually be spaced. Sow the seeds, covering them by about their own depth with soil. By sowing in drills it is then easy to determine which seedlings are annuals and which are weeds in the early stages of growth. As the annual seedlings grow they should be thinned to final spacing in the row equal to the spacing between the rows.

Philip Swindells has over 40 years gardening experience. A former botanical garden curator and an international horticultural consultant, he has worked extensively overseas. The Author of more than 50 gardening books, he has been awarded a Quill and Trowel Award by the Garden Writers