- Annuals are flowers which grow from seed to flower and seed again in one year.
- Biennials take two years to grow from seed to flower and seed again.
- Perennials go on year after year once planted.
Hardy annuals are sown where they are to grow in March or April, depending on the weather. These include cornflower, sweet sultan, love-in-a-mist, sweet pea and sunflower
Some hardy annuals which can take a hard winter can be sown outdoors in late summer. These include marigolds and many wild flowers.
Half hardy annuals cannot be grown out of doors until all danger of frost has passed. These include the morning glory, lobelia and snapdragon.
You can cheat by sowing these indoors and planting them out later, or buying ready-grown half-hardy plants from garden centres. Half-hardy plants are usually grown in hanging baskets and window boxes.
Hardy perennials like michaelmas daises and golden rod will go on year after year, but their vegetation will die down in the autumn and when their clumps get over-large they will need dividing.
Perennials should be given a season to settle in, they won’t be at their best in the first year.
Cadge free perennials from fellow gardeners in the autumn or spring when they are dividing up over-large plants. Only plant outside pieces of root, not the woody centres.
Half-hardy perennials like geraniums and fuchsias must be taken indoors before the first frosts in autumn.
Allow perennials a season to settle in, they won’t be at their best in the first year.
Establish clumps are useful in filling beds of shrubs as they are big enough to show up against them, and will go on for year after year without much attention.
Put tall perennials like delphiniums at the back of a border, always check on the ultimate height of a plant before placing it.
Don’t forget tall flowers may need staking in windy conditions, but many of them, golden rod and even the sun flower for instance, now come in dwarf versions.