Annuals germinate, grow, flower, set seed and die within one year, often much less. You may find that some plants, such as snapdragons (Antirrhinum) and tobacco plants (Nicotiana) which are referred to as annuals last more then a year. This is because they are actually perennials but usually perform better if grown as an annual. By the second year they may become straggly and not flower so well.
Annuals are often referred to as ‘bedding plants’ as they are usually grown from seed in greenhouses or nursery beds and then moved to their final position as small plants. You can either grow your own from seed or buy small plants.
All annuals (including perennials grown as annuals) are divided into two groups according to their hardiness:
1. Hardy plants will survive frost and can be sown directly outside where they will flower. Many, such as love-in-a-mist (Nigella) and sweet peas (Lathyrus odoratus) can be sown the previous autumn for larger plants and earlier flowering. Many will self-seed and come up again in subsequent years.
2. Half-hardy plants cannot be planted out until the risk of frost has passed. Most also need a temperature of 10 C/50 F to germinate. For this reason the seeds need to be started off under glass but a warm window sill will do just as well as a greenhouse.
Care for Annuals in Your Garden
Annuals are very easy to look after but because their life cycle is so short they have some requirements which you cannot ignore.
– Most annuals need sun, and only busy Lizzies (Impatiens) and tobacco plants (Nicotiana) will do well in deep shade.
– Many annuals grow fast – sunflowers (Helianthus annus) will reach over 2 m/6 ft, and need support right from the start. If you let tall annuals flop and fall they will grow crooked or even die if their stems are damaged. They grow so quickly that they need to get it right the first time.
– Most annuals need regular supplies of water. This is especially important for plants in containers and hanging baskets which can dry out very quickly.
– Many annuals will flower better if you regularly feed them with an organic supplement such as tomato food. This will encourage the plant to produce more blooms over a longer period and the supplement can easily be added to their water.
– Many annuals need deadheading regularly if you want them to flower throughout the summer.
All this may make it seem as if annuals are difficult to grow but they are very useful and do give a lot in return for a little care.
– Annuals will fill in gaps while slower growing shrubs become established. Big plants like sunflowers (Helianthus annus) will fill spaces, and sweet peas (Lathyrus odoratus) or even runner beans will attractively cover a blank fence quickly.
– Annuals will provide almost instant color and can be used to extend the interest in a bed.
– As annuals are short-lived you can vary your display each year.
– Annuals are ideal for containers as they can be used to create year-round color and interest. A pot with a shrub in it can have a succession of annuals planted around the base which will do the main plant no harm and keep the pot looking good long before or after the shrub has flowered.