Are you looking for an explanation of the difference between annual vs. perennial plants? This article will demystify the jargon and help you to make an informed choice next time you’re buying plants.
One of the brilliant things about gardening as a hobby is that it’s so accessible to anyone who wants to have a go. Even if you don’t have your own garden, there are lots of great ways to get stuck in: allotments, community gardens, and gardening in containers are all fantastic ways to enjoy gardening and learn a new hobby.
Having said that, the world of gardening does have its own set of terms and phrases that can be bewildering at times. If you’re new to gardening, or simply not familiar with the terminology, it’s completely understandable that you might feel a little confused.
A guide to annual vs. perennial plants
Buying plants is probably one of the first things we do when we start gardening, and while browsing and choosing your plants is a lot of fun, it can also be a bit of a minefield when it comes to deciphering the vocabulary. That’s where this quick guide will come in very handy!
Annual vs. perennial plants
Here’s an explanation of the main categories used to classify plants, and what they mean.
We’ll start with annual vs. perennial plants as these are the two most common categories, but we’ll also cover a third category called biennials.
What is an annual plant?
Annual plants complete their life cycle of growing, flowering, and dying back in one growing season.
As their name suggests, they’re usually a one-year thing, and need to be replaced regularly.
Meaning of annual plants
Annuals are often referred to in shops as ‘bedding plants’. Those multipacks of small plants you find at the garden centre, DIY shop, supermarket, or online, are highly likely to be bedding plants.
There are summer annual plants, and winter annual plants. The season refers to the time of year that the plant is in flower.
Do annuals come back every year?
As a general rule, annual plants don’t survive into a second year. However, some annual plants are able to survive if you grow them in a sheltered spot and take good care of them. It’s best to assume that your annual plants aren’t a long-term investment though, and treat annual flowers that come back every year as a bonus.
Do you have to dig up annuals?
Annual plants that have died won’t usually grow again, so it makes sense to dig them up. Removing them will create space for other plants and keep the garden looking tidy.
Advantages of annual plants
There’s lots to love about annual plants. Here are the main reasons why they can be a good option for your garden or outdoor space.
- Cost. Annual plants are usually quite cheap to buy. This means you can use them to perk up a container or border without spending a fortune.
- Variety. There are loads of different varieties to choose from, including annual plants with impressive flowers, lovely scent, or striking foliage.
- Easy to take care of. Most annual plants sold are pretty low maintenance, and don’t need specific compost or growing conditions. This makes them perfect for beginner gardeners and people who don’t have lots of time to dedicate to gardening.
- Compact. Annual bedding plants can be grown very successfully in containers and small areas, so if you’re gardening in a compact space they’re ideal.
- Flexibility. Like the idea of being able to change your planting scheme regularly? Annual plants give you the flexibility to do this.
Disadvantages of annual plants
- False economy. Annual plants are cheap, but you have to keep replacing them. This can make using annual plants quite expensive in the long run.
- Ongoing maintenance. You need to dedicate time to replacing annual plants on a regular basis. If you want to limit the garden maintenance, this probably isn’t ideal.
- Tender plants. Summer annual plants are unable to tolerate cold conditions, and will need protection when temperatures drop.
Popular examples of annual plants
Here’s a list of some of the most popular annual plants.
Flowering annual plants
- Pansies & violas
- Sweet peas
Foliage annual plants
- Hypoestes (polka dot plant)
- Ornamental cabbage & ornamental kale
Edible annual plants
What is a perennial plant?
Perennial plants carry on growing year after year.
Unlike annual plants, they will continue to look good for a number of years after you plant them, so you shouldn’t need to replace them very often.
Meaning of perennial plants
Perennial plants are usually categorised in the following ways: herbaceous (dies back over winter), hardy (able to tolerate frost), tender (unable to tolerate cold conditions), woody (trees and shrubs), and semi-woody (forms a woody stem and base).
Do perennials come back every year?
Lots of varieties of perennial plant will die back over winter; this is called a dormant phase. When the weather warms up they start to grow again.
Advantages of perennial plants
If you’re wondering ‘Why are perennials better than annuals?’, here are some key reasons why perennial plants might be the right choice for you.
- Cost effective. Perennial plants tend to be more expensive than annual plants, but because you don’t have to replace them every year they can end up costing you less in the long term.
- Variety. As with annual plants, you’ll be spoilt for choice when shopping for perennials.
- No need to rethink the garden regularly. Once you’ve planted a perennial plant, it will continue to grow and look good in a border or pot. This means there’s less work required to keen the garden looking good.
- Wide range of sizes. Whatever space you have available, there’ll be a perennial plant that can fill it. Perennials are a particularly good option if you’re gardening in a large area.
- Good for wildlife. The fact that perennial plants are around for longer means they can provide a source of food and shelter for wildlife over a number of years. If you want to make your garden more wildlife-friendly it’s worth taking this into account.
Disadvantages of perennial plants
- High initial cost. Perennial plants usually cost more than annual plants, this is because they are either bigger, or take longer to grow. If you don’t have a big budget this could be an issue.
- Maintenance. You need to be prepared to feed and prune perennials plants throughout their life span.
- Not very flexible. Moving a perennial always involves a risk of losing the plant. If your garden is a work-in-progress you should think carefully about where and when you introduce perennial plants.
- Winter dormancy. As I mentioned earlier, many varieties of perennial plant are dormant during the colder months of the year, leaving bare patches in your pots and borders. You may feel the need to fill these gaps with bedding plants.
Popular examples of perennial plants
See how many of these perennial plants you have in your garden.
Flowering perennial plants
- Aster (Michaelmas daisy)
- Japanese Anemone
- Oriental poppy
Foliage perennial plants
- Creeping Jenny
- Ornamental grasses
Edible perennial plants
- Sprouting broccoli
What is a biennial plant?
Biennial plants complete their life cycle of growing, flowering, and dying back in a two year period.
In the first year, the seeds of biennial plants start to grow, then the plant stays dormant over winter. In the second year, the plant flowers and dies back.
Do biennials flower every year?
No. Biennial plants flower in their second year, but not their first.
If you want a particular variety of biennial plant to flower in your garden every year, you need to stagger the planting.
How many years do biennial plants live?
Biennial plants live for a total of two years, after which time they will set seed and die.
Advantages of perennial plants
- Grow from seed. If you like the idea of growing flowers from seed, biennials are a good option.
- Cost. Biennials can be grown from seed, or bought as small plants which you then grow on at home. This makes them a cost-effective way to buy plants.
- Self-seeding. Many varieties of biennial plants will seed themselves in your garden, so you can increase your plants and enjoy biennials year after year for basically zero effort or cost.
Disadvantages of biennial plants
- Long wait time. You need to be patient with biennials as you won’t get quick results.
- Storage. Many biennial plants do best when the small plants are stored over winter and planted out in spring. This means you may need a cold frame or greenhouse to keep them in.
- Maintenance. Young biennial plants will need regular attention to keep them healthy until they are ready to grow and flower in their second season.
What advantages do biennials have over annuals?
The main advantage that biennials have when compared to annual plants is that they can usually deal with cold weather more easily. The other thing to bear in mind is that, unlike annuals, biennials are pretty good at self-seeding.
Popular examples of biennial plants
You might be surprised by just how many common biennial plants there are.
Flowering biennial plants
- Forget me nots
Edible biennial plants
- Some varieties of lettuce
- Brussels sprouts
Why is it important to understand the difference between annual and perennial plants?
Knowing which type of plant you’re buying will help you to understand just how long it will be before you are going to have to replace the plant.
Understanding annual vs. perennial flowers and plants will also help you to control how much you spend on your gardening hobby. Perennial plants are usually the more cost-effective option in the long run, so they’re great if you’re gardening on a budget.
Annual vs. perennial vs. biennial
Knowing which of your plants are annuals, and which are perennials or biennials, also allows you to care for them in the right way. For example, if an annual plant dies back you would probably need to remove it, but if it’s a perennial plant that would be a mistake because it will grow back again next year.
What is the difference between perennial and annual? A summary
Annuals live for one year
Biennials live for two years
Perennials live for three years or more
Is it better to plant annuals or perennials?
You might be wondering whether it’s a good idea to combine annual plants with perennial plants and biennial plants in your garden. The answer is yes!
I think a good approach is to use perennials to create the basis of your planting scheme, then add in annual plants and biennial plants when and where you need to.
Perennials will give your garden its structure, and can also provide colour, texture, scent, height and privacy.
Annuals and biennials are fantastic for filling gaps, giving borders and containers a new lease of life, and generally providing colour and interest when things start to look a little drab.
Annual or perennial?
By growing annual and perennial plants you can benefit from the advantages of both options, while limiting their disadvantages. It also gives you access to an even bigger range of lovely plants!
Right plant, right place
Whether you’re planting annuals, biennials, or perennials, it’s really important to choose the most suitable place for them. In the gardening world this is often referred to as ‘right plant, right place’.
Every variety of plant has it’s own set of conditions that it prefers to grow in. That could be full sun, partial shade, full shade, sheltered, exposed, damp soil, dry soil, poor soil, and so on.
To help your plant thrive, you need to grow it somewhere that provides its ideal conditions. The plant label will tell you what these are, or you can look it up online or use a plant identification app.
If you force a plant to grow in less-than-ideal conditions, it will struggle to do well.
So basically, if you want to get the most out of your plants, read those care instructions and do your best to choose a really good spot in the garden for them. If you can’t provide the right conditions, it’s time to choose a different plant.
Hopefully this guide to perennial vs. annual plants has helped you understand the differences, and made it easier for you to buy the right plants for your garden or outdoor space. Happy plant shopping 🙂
More useful gardening guides
If you’d like to explore more gardening and plant advice I’ve got lots of other useful blog posts for you.
My guide to dividing perennial plants shows you another easy way to make new plants for free.
If container gardening is your thing, I’ve got a whole series of the best plants for each season. There are lists of the best spring flowers for pots, summer plants for pots, fall flowers for pots, winter plants for pots and plants for winter hanging baskets. I’ve also written guides to low maintenance plants for outdoor pots, trailing plants for hanging baskets, and growing wow factor hanging flower baskets that are useful all year round.
For extreme summer heat, you need my roundup of drought tolerant plants.
If you’ve enjoyed this post and found it useful, here are some ways you can say thanks and support Growing Family:
🌻 Click here to sign up to my newsletters and get regular updates straight to your inbox.
🌻 Share this post with your friends via the buttons below.