The Uses of Annuals and Biennials

Annuals are probably most widely used for filling gaps in borders, on the rock garden and elsewhere, for they provide splashes of welcome color in a matter of months. A bed or border devoted entirely to hardy annuals can make a splendid carpet of color during the summer months, but it does entail considerable work in weeding and maybe watering in the early stages.

For a small garden or one of moderate size, a mixed border of hardy herbaceous perennials and annuals will provide interest and colour from May to October without undue toil.

With both types of plants it is possible, by making a careful choice, to include only such plants as require no staking and it is wise, in exposed gardens, to use low-growing plants that will not be battered by summer gales. (A list of such plants is given later.)

New gardens

One of the quickest ways of making a display in a new garden is by sowing hardy annuals, for seed sown in April where it is to flower will give a display from June onwards.

The choice of annuals is very wide and the range of colour all embracing which gives ample scope for those with bright ideas and those who like to try something different each year.

Containers

For those whose gardening may be confined to window boxes, tubs or other containers on a roof garden or in a patio, half-hardy annuals are probably the best bet. These can be planted out as young plants in May and will soon start to flower.

This is much more satisfactory, although it costs more than sowing seed of hardy annuals in window boxes which are usually too exposed for young seedlings to make good plants, even though the seed may germinate reasonably well in the first place.

Suitable half-hardy annuals for growing in containers are antirrhinum, petunia, fragrant stocks, annual chrysanthemum, cherry pie (heliotrope), lobelia, Phlox drummondii, African and French marigolds and other showy plants.

Hanging baskets are also most decorative when filled with heliotrope, trailing lobelia, free-flowering nasturtium, petunia and other summer-flowering plants.

Edging and paving

Other uses of annuals are as dwarf edging plants for the front of a bed or border, or for sowing in crevices in paving.

Among these is the low-growing Limnanthes douglasii with quite large white flowers with a yellow center, which seeds itself without becoming a nuisance, mesembryanthemtun with gay daisy-like flowers that thrives in well-drained soil and full sun, anagallis (pimpernel), and the creeping zinnia, Sanvitalia procumbens, with single yellow flowers with a black center on 6 in. stems. This curious little plant is like a miniature sunflower and never fails to attract interest.

Cut flowers

Annuals provide a splendid selection of flowers for cutting and with a little planning flowers can be available over a long period. By sowing hardy annuals in the open in the autumn and making another sowing in the open in the spring a succession of welcome flowers will be assured. A list of annuals for cutting is given later.

Biennials are also most useful and effective in a border, particularly when planted in bold clumps. Wallflowers are probably among the most popular and there is a splendid range of colour. The fragrance on a warm day in May is glorious.

For small gardens the ‘Tom Thumb’ varieties, about 9 in. high, are most valuable and decorative. These and other biennials are best planted in their flowering positions in the early autumn, but if necessary this can be deferred until March.

If the winter happens to be severe, spring planting will prove to be the right choice, but autumn planting gives the wallflowers and other biennials more time to get established, in a reasonable winter.

Groups of Sweet William in well-drained soil and a sunny position are delightful in early summer, and they are also useful for cutting. Other popular biennials include Canterbury bell, the blue cynoglossum with forget-me-not-like flowers borne on in curling sprays, polyanthus in many rich colors, honesty with its large flat seed pods which make decorative material when dried, Iceland poppy (Papaver nudicauk) and many different violas and pansies.