At Fothergill's, we believe gardening is for everyone. From woody shrubs plants to pretty flower plants and tasty veg, there are many wonderful plants that are easy to grow in British gardens, even for complete beginners.
But if you're new to gardening, it can be tricky to know where to start, especially when it comes to understanding the terminology. For example, what does 'hardy annual' mean? What's the difference between perennials and biennials?
Don't worry – these terms might sound technical, but they're actually quite simple to understand. In this guide, we’ll talk you through various different types of plants and seeds, including annuals, perennials, and biennials. Once you’re familiar with these key plant classifications, you'll be well on your way to creating the garden of your dreams!
What Are Annual Plants?
Annual seeds and plants complete their entire life cycle – from seed to flower to seed again – in just one growing season. In other words, they die at the end of their first year rather than lying dormant to grow again.
While annual flowering plants are short-lived, they're often the show-stoppers of the British garden. They typically bloom from late spring right through to autumn and can produce some of the biggest, brightest, and most spectacular flowers you'll ever see! Most vegetable plants, such as tomatoes and cucumbers, are also annuals.
Some annuals – including many native British wildflowers – will reliably self-seed, surprising you by sprouting new plants the following season. Others, such as F1 hybrid varieties, have to be replanted each year.
What Are Hardy Annual Plants?
Hardy annual plants are annuals that can withstand cold temperatures and frosts, making them ideal for the UK climate. They can usually be sown directly into the ground outside, where they are to grow, as they won’t be killed off by a sudden cold snap! However, if germinated indoors, they should still be introduced to the outdoors gradually.
Most hardy annual seeds are sown in late autumn/winter or early spring, depending on the variety. Some popular options include:
If you don’t want to sow seeds, you can also buy hardy annuals as young flowering plants, which will take less time to grow and bloom.
What Are Half-Hardy Annuals?
Half-hardy annuals are annuals that are more sensitive to cold and cannot survive frost. Unlike their tough, hardy cousins, these plants need a bit more care and protection in the UK's cool climate.
Typically, you'll need to sow half-hardy annual seeds indoors or in a heated greenhouse and only transplant them outside once the weather has warmed – usually around late May or early June. Some varieties, though, can be sown outside once the risk of frost has passed. Examples of half-hardy annual seeds include cosmos seeds, zinnia seeds, and French marigolds.
What Are Perennial Plants?
Perennial seeds and plants live for more than two years, coming back season after season. They're the mainstays of British flower beds and borders, typically growing a bit more slowly but becoming larger and more impressive over time.
Herbaceous perennials die back to the roots in autumn before regrowing completely the following spring. Woody perennials, however, have woody stems that remain above ground during winter – some, called evergreen perennials, will even keep their leaves. You can also get perennial vegetables, like asparagus and perpetual spinach.
Perennials are known for being reliable, low-maintenance plants, and they make a great investment for gardeners as you don’t have to replant them each year. Once established, they need very minimal care and attention to keep them looking great!
What Are Hardy Perennials?
Hardy perennials, like hardy annuals, can survive frost and freezing temperatures. These plants will happily live outdoors in British gardens all year round, going dormant during winter and then springing back to life in spring with fresh growth and flowers.
You can sow hardy perennial seeds directly outdoors or propagate them indoors for a faster start if you prefer. Popular varieties include:
As with annuals, you can also buy hardy perennial plants if you don’t want to wait for seeds to germinate. Many flower bulbs and tubers are also hardy perennials, such as daffodils and crocuses.
What Are Half-Hardy Perennials?
Half-hardy perennials won’t survive a frost, so they’ll need some protection over winter to ensure they return year after year. This may mean adding a thick layer of mulch over the roots, or even digging the plants up and bringing them indoors until spring.
Sometimes, you might see half-hardy perennial plants referred to as ‘tender perennials’. Technically, they’re slightly different: half-hardy perennials can tolerate cold and wet weather but not frost, whereas tender perennials won’t survive low temperatures at all. However, they are often grouped together into one category (especially in the UK, where frost and freezing temperatures go hand-in-hand). Examples include pelargoniums (‘tender geraniums’) and dahlias.
What Are Short-Lived Perennials?
As their name suggests, short-lived perennials don’t live for as long as other perennial flowers and plants. They will bloom for a few years but will then start to decline and eventually die. Most gardeners consider any perennial that lives for less than five years to be short-lived, though there’s no strict definition.
Many short-lived perennials are treated as annuals and replaced every year. Tulip bulbs are a classic example – while technically perennials, they often don’t flower reliably after their first season.
What Are Biennial Plants?
Biennial plants take two years to complete their life cycle: they spend their first year in active growth before blooming beautifully in their second year. They’ll die after flowering, though some biennials will self-seed to produce new plants.
Most biennial seeds are sown from April to July, giving seedlings time to grow and build their energy stores before winter. Like annuals and perennials, they may be hardy, half-hardy or tender – less hardy varieties may benefit from germinating indoors.
If you’re looking to grow biennials, some popular options include Sweet William seeds and Digitalis (foxglove plants.)
Shop Seeds and Plants at Fothergill’s
Now you’re familiar with the different types of seeds and plants, it’s time to get growing! At Fothergill’s, we stock a fantastic range of flower seeds, bulbs and plants for home gardeners, as well as vegetable seeds, fruit seeds, and so much more. All of our products come with full growing instructions to help you achieve fantastic results, whether you’re a gardening novice or a green-thumbed expert.
Shop online today for fast UK delivery, or head to our gardening blog for more growing tips!
