Nasturtiums: Annuals or Perennials?
Many gardeners enjoy the cheerful, bold colours of nasturtiums, but a common question arises: do nasturtiums come back every year? The straightforward answer for most climates is no; nasturtiums (Tropaeolum majus) are generally grown as annuals. While they produce seeds that can self-sow, meaning new plants might appear the following spring, the original parent plant typically does not survive frost and return from its roots.
- Nasturtiums are primarily grown as annuals.
- Parent plants usually die back after the first frost.
- Self-seeding can lead to new plants each year.
- Propagation via cuttings or seed offers more control.
This classification as annuals is key to their widespread appeal and ease of cultivation. They germinate readily, grow quickly, and produce a profusion of flowers throughout the warmer months, making them a reliable choice for adding instant colour to borders, containers, and hanging baskets. Their distinctive, shield-shaped leaves and trumpet-like flowers in shades of yellow, orange, red, and deep crimson are instantly recognisable and add a touch of informal charm to any garden space. If you are looking for plants that reliably reappear year after year without intervention, you might need to consider other options, or learn how to encourage your nasturtiums to continue their presence.
The desire for plants that return annually is understandable. It saves time, effort, and expense compared to replanting each season. However, the short life cycle of nasturtiums contributes to their prolific flowering. Instead of investing energy into surviving winter, they focus on producing flowers and seeds to ensure the continuation of the species. Understanding this life cycle is the first step towards either accepting their annual nature or actively managing them for continued presence.
Encouraging Self-Seeding
While the parent plant won't survive a harsh winter, nasturtiums are exceptionally good at producing seeds. If you allow the flowers to mature and form seed pods, these pods will eventually split and scatter their seeds. In milder climates, or if protected by mulch, some of these seeds may successfully overwinter and germinate the following spring. This natural process can give the appearance that the nasturtiums have returned, when in fact, they are new plants grown from the previous year's seed drop. To maximise this effect, avoid tidying up too much in the autumn, allowing seed heads to mature and disperse naturally.
The success of self-seeding depends heavily on your local climate and garden conditions. Heavy frosts can kill germinating seedlings, and deep mulch can sometimes smother them. If your goal is to have nasturtiums return each year with minimal fuss, leaving some of the spent plants in place over winter and scattering a few extra seeds in autumn can increase your chances. It’s a charmingly unpredictable way to garden, but it doesn’t guarantee a return of your specific plants.
The key to enjoying nasturtiums year after year lies in understanding their life cycle and embracing methods to ensure their continued presence, rather than relying on the original plants to survive.
When to Sow Nasturtium Seeds
Since they are treated as annuals, nasturtiums are typically sown directly into the ground after the last frost has passed. Their seeds are quite large and germinate easily. In the UK, this usually means sowing from April onwards, once the soil has begun to warm up. You can start them off indoors a few weeks earlier in pots, but they transplant best when young and are not particularly fussy about being moved. Sowing directly outdoors is often preferred to minimise root disturbance and ensure a robust start for the young plants.
The growing season for nasturtiums is relatively long. They thrive in full sun but can tolerate partial shade, especially in hotter climates where a little shade can prevent scorching. They prefer well-drained soil and can tolerate poorer soil conditions, which is one reason they are so forgiving. In fact, overly rich soil can encourage more leaf growth at the expense of flowers. This resilience makes them a popular choice for beginner gardeners and for filling gaps in borders where other plants might struggle.
How to Keep Nasturtiums Coming Back
If you're wondering how to ensure nasturtiums come back every year, beyond relying on self-seeding, there are two primary methods: collecting and saving seeds, or taking cuttings. Both approaches offer more certainty than natural dispersal. Saving seeds is straightforward and allows you to plant the exact same varieties or colours the following year, ensuring continuity and colour schemes.
To collect seeds, wait until the flowers have faded and developed into small, round, greenish seed pods. Once these pods turn brown and dry, and before they split open, carefully pick them off the plant. Store them in a cool, dry place in paper bags or envelopes, clearly labelled with the variety and date. Ensure they are completely dry to prevent mould. These seeds should remain viable for several years, giving you a reliable source for next spring's planting.
Save nasturtium seeds from your healthiest, most vigorous plants to propagate desirable traits for the following year.
Taking Cuttings from Nasturtiums
Nasturtiums can also be propagated vegetatively through cuttings. This method is particularly useful if you want to preserve a specific, unusual colour or growth habit that might not come true from seed, or if you live in a very cold climate where saving seeds is less reliable. The process is similar to taking cuttings from many other common bedding plants.
In late summer or early autumn, before the first hard frost, take cuttings from healthy, non-flowering shoots. These cuttings should be about 10-15 cm long. Remove the lower leaves, and dip the cut end in rooting hormone if desired, though nasturtiums often root without it. Insert the cuttings into pots filled with a moist, well-draining potting mix, such as a peat-free compost mixed with perlite or grit. Water them gently and place the pots in a warm, bright location, but out of direct sunlight. Covering the pots with a plastic bag or propagator lid can help maintain humidity, which is crucial for successful rooting. Keep the compost consistently moist. With luck, roots will form within a few weeks, and these new plants can then be overwintered in a frost-free location, such as a cool greenhouse or bright windowsill, ready to be planted out the following spring.
This approach allows you to guarantee the return of your favourite nasturtiums, bypassing the uncertainties of seed germination and overwintering.
Overwintering Nasturtium Plants
While parent plants are unlikely to survive a typical British winter outdoors, it is possible to overwinter them under protection. If you have a greenhouse, cold frame, or even a very bright, frost-free windowsill, you can attempt to keep established plants going. This involves either repotting a healthy specimen plant, or, as mentioned, overwintering rooted cuttings. Reduce watering significantly during the winter months to prevent waterlogging and root rot, and ensure good air circulation to deter fungal diseases. Growth will slow considerably, but the plant will be ready to resume vigorous growth and flowering when spring arrives and conditions improve.
This method requires a bit more effort and space but can be rewarding. The overwintered plants may not be as vigorous as young plants grown from seed, but they will establish faster in the spring. If you are considering this, ensure you choose a healthy, disease-free plant to start with. Pests like aphids can be a problem, so inspect plants carefully before bringing them indoors or into protected environments.
Alternatives to Nasturtiums for Perennial Colour
If your heart is set on flowers that reliably return every year without much fuss, there are numerous perennial alternatives that offer vibrant colours and interesting foliage. While nasturtiums are beloved for their informal charm and edible flowers, perennials provide a more stable, long-term planting scheme. They establish a strong root system over time, allowing them to withstand varying weather conditions and return year after year.
When considering alternatives, think about the conditions in your garden. Do you have full sun, partial shade, or damp soil? Matching plant requirements to your site is fundamental to success. For instance, if you love the bright orange hues of nasturtiums, you might look at plants like Potentilla, Hemerocallis (Daylilies), or even some varieties of Rudbeckia. For cheerful yellow flowers, Coreopsis or Geum could be excellent choices. The key is to select plants that are known for their hardiness and longevity in your specific growing zone.
Perennial Flowers for Sunny Borders
For gardeners seeking dependable colour in sunny spots, several perennials rival the cheerfulness of nasturtiums. Coneflowers (Echinacea) offer daisy-like blooms in vibrant pinks, purples, and whites, and are a magnet for pollinators. Salvias provide spikes of colour for extended periods, often in shades of blue, purple, and pink. Sedums, particularly the 'Autumn Joy' varieties, offer late-season interest with their sturdy stems and succulent flower heads that transition from pink to a deep rust colour. These are also excellent for attracting bees and butterflies.
If you appreciate the trailing habit of some nasturtium varieties, consider trailing Lobelia for vivid blue or white flowers, though these are often treated as annuals but can sometimes overwinter in milder areas. For climbing or rambling plants, Clematis varieties offer spectacular displays, and many are truly perennial. Even some types of Geranium (hardy geraniums, not pelargoniums) offer long-lasting ground cover and attractive flowers in shades of pink, purple, and white, and are generally very robust.
Choosing hardy perennials simplifies garden maintenance and ensures a consistent display of colour and texture season after season.
Perennials for Shady or Mixed Borders
Nasturtiums can tolerate some shade, and if you're looking for shade-tolerant perennials, there's a wealth of options. Hostas, while primarily grown for their striking foliage, also produce elegant flower spikes in summer. Astilbes offer feathery plumes of colour in shades of pink, red, and white, thriving in moist, shady conditions. Ferns provide beautiful architectural foliage, adding texture and structure without the need for bright flowers. Impatiens, though often treated as annuals, can perform well in shade and some varieties are exceptionally long-flowering.
For areas with dappled shade, consider Hellebores (Winter or Lenten Roses), which bloom in late winter to early spring, providing colour when little else is flowering. Columbines (Aquilegia) offer delicate, intricate flowers in a wide array of colours and often self-seed readily, behaving somewhat like annuals but returning reliably from established root systems. These provide a different kind of charm to nasturtiums, with a more refined and delicate appearance.
Edible Perennials and Companion Planting
Nasturtiums are famously edible, with their peppery leaves and flowers adding a punch to salads. If this is a key feature for you, consider other edible perennials. Rhubarb offers tart stems for cooking, and its large leaves can create a dramatic backdrop. Mint varieties spread vigorously and provide fresh leaves for culinary use or teas. Chives offer mild onion flavour and attractive purple flower heads that are also edible. For edible flowers, consider Pansies and Violas; while often grown as annuals or biennials, they can sometimes perenniate in mild conditions and offer delicate, sweet flavours.
When thinking about companion planting, nasturtiums are often cited for deterring pests like aphids and whiteflies from certain vegetables. If you’re looking for perennial companions that offer similar benefits or simply complement your vegetable patch, consider borage, which attracts pollinators and has edible flowers. Lavender is excellent for attracting beneficial insects and its scent can deter pests. Marigolds (Tagetes) are known for their pest-repelling properties, and while many varieties are annuals, some can behave as short-lived perennials in sheltered spots.
Understanding Nasturtium's Life Cycle
To fully appreciate why nasturtiums are not typically perennials, it's helpful to delve deeper into their natural life cycle. As annuals, their entire existence from seed to seed occurs within a single growing season. This rapid development cycle means they are perfectly adapted to areas with short, warm summers. They germinate quickly, grow rapidly, flower abundantly, and produce seeds, all within a few months.
In temperate climates, like much of the UK, the challenge for a nasturtium plant is surviving the winter. Their roots are not robust enough to withstand freezing temperatures and waterlogged soil. As soon as the first significant frost arrives, the plant's tissues will be damaged, and it will begin to decay. This is why, even if a few seeds manage to sprout early in spring, the original plant will have succumbed to the cold the previous autumn or winter.
Plant nasturtiums in well-drained soil to prevent root rot, especially if you are hoping for some self-seeding to occur.
Why They Are Grown as Annuals
The classification of nasturtiums as annuals is primarily horticultural. While botanically they might be tender perennials in their native South American habitats (which are warmer and have different winter conditions), they simply cannot survive prolonged cold or frost in most garden settings. Therefore, gardeners treat them as annuals, sowing them fresh each spring. This approach is also advantageous because it allows for a consistent display of vigorous, flowering plants each year, rather than potentially struggling with older, less productive plants.
This annual nature means that, unlike true perennials such as peonies or hostas, you don't need to worry about dividing them or preparing them for long-term survival. Their relatively short lifespan is their defining characteristic, and it’s what makes them such a popular and accessible choice for immediate, impactful colour. When you plant nasturtiums, you are investing in a season's worth of vibrant blooms and foliage, with the understanding that their cycle will conclude with the changing seasons.
The predictable outcome of nasturtiums dying back after frost is precisely why they are so widely available as seed packets or young plants each spring.
Comparing Nasturtiums to Other Garden Flowers
To further illustrate, consider the difference between nasturtiums and other common garden flowers. For example, pansies and violas are often grown as annuals or biennials. While they may survive a mild winter in sheltered spots, they are generally replanted or treated as short-lived. In contrast, true perennials like lavender, salvias, and echinacea are planted once and are expected to live for many years, growing larger and more established each season. If you're comparing nasturtiums to flowers like cosmos or zinnias, they share a similar annual life cycle, often sown directly in spring and enjoyed until autumn. However, cosmos and zinnias typically have a longer blooming period and are also prone to frost damage, reinforcing their annual status.
For those interested in propagation, the difference between annuals and perennials becomes even more pronounced. Perennials are often propagated by division or cuttings to maintain their characteristics, whereas annuals are primarily grown from seed, which allows for greater genetic diversity and the development of new cultivars. Understanding these distinctions helps gardeners make informed choices for their planting schemes, whether they seek the fleeting beauty of annuals or the enduring presence of perennials.
Conclusion: Enjoying Nasturtiums Annually
So, to definitively answer the question: do nasturtiums come back every year? For the vast majority of gardeners, the answer is no, they do not return as the same plant from the previous season. They are best treated as annuals. However, this doesn't mean you can't enjoy their vibrant presence year after year. By understanding their life cycle, you can actively encourage their return through saving seeds, allowing self-seeding, or even taking cuttings to overwinter.
Whether you choose to sow fresh seeds each spring, rely on nature's generosity for self-sown seedlings, or preserve your favourite specimens, nasturtiums offer a rewarding and colourful addition to any garden. Their ease of growth, beautiful foliage, edible components, and cheerful blooms make them a favourite for good reason. Embrace their annual nature, and you’ll find it simple to keep these delightful flowers gracing your garden beds and containers season after season.
If the idea of plants that reliably return appeals more strongly, exploring the wide world of perennial flowers offers an excellent alternative. By selecting species suited to your climate and garden conditions, you can build a garden that provides continuous colour and structure with less annual effort. But for the unique charm and bright, informal beauty of nasturtiums, a little planning each year is a small price to pay for their delightful contribution.
Ultimately, while nasturtiums are not perennials, their prolific seeding and ease of propagation make them a garden staple that can be enjoyed anew each season.
Garden Planning with Nasturtiums
When planning your garden, consider where nasturtiums will fit best. They excel in containers, hanging baskets, window boxes, and borders. Their trailing varieties can spill over walls or edges, while bush types provide upright colour. They pair well with many vegetables, acting as a trap crop for aphids or a companion to deter pests. Consider planting them near brassicas, beans, or tomatoes. Their vibrant colours also make them excellent companions for less showy plants, providing a lively contrast and filling gaps in beds as other plants mature. Their inclusion adds a dynamic, cheerful element that changes with each planting.
If you are interested in companion planting for vegetables, nasturtiums are a great choice. They can be planted around the base of plants like cucumbers or squash to deter squash bugs. Their edible flowers and leaves can also be used in salads or as garnishes, adding a peppery zest to your culinary creations. This dual purpose – ornamental and edible – further enhances their value in an organic or wildlife-friendly garden. Their ability to thrive in less fertile soil also means they won't compete heavily with more demanding vegetable crops for nutrients.