The Enchanting World of Verbena bonariensis: A Tall, Unusual, but Beautiful Perennial for UK Gardens

When you think of adding a perennial to your garden, the usual suspects probably come to mind: roses, lavender, geraniums, or perhaps a well-behaved shrub. But what if I told you there’s a stunning, statuesque perennial that brings not just beauty but a touch of magic to your garden? Meet Verbena bonariensis, a perennial that stands tall and proud, offering unique charm, a feast for pollinators, and a perfect backdrop for other garden plants.

While not as well-known as your typical cottage garden favorites, Verbena bonariensis is gaining popularity among UK gardeners who appreciate its unusual yet captivating presence. In this blog post, we’ll dive deep into the enchanting world of Verbena bonariensis, exploring its origins, how to grow it, why it’s a perfect addition to your UK garden, and how it can transform your outdoor space into a haven for both plants and wildlife.

So, let’s get to it, and discover why this South American beauty deserves a prime spot in your garden!

A Tall Beauty: What Is Verbena bonariensis?

Verbena bonariensis, also known as purpletop vervain or Argentinian vervain, is a perennial plant native to South America, particularly Argentina and Brazil. Despite its exotic origins, this perennial has adapted beautifully to the UK climate, thriving in gardens across the country. Verbena bonariensis is loved for its airy, tall stems and clusters of tiny, vibrant purple flowers that bloom from mid-summer through to the first frost.

The Unique Appeal of Verbena bonariensis:

Tall and Airy Structure: One of the most striking features of Verbena bonariensis is its height. It can reach up to 6 feet (around 180 cm) in height, with slender, wiry stems that remain mostly leafless. This gives it an ethereal, floating quality, as if the flowers are hovering above the rest of the garden.
Long Blooming Period: While many perennials have a relatively short blooming season, Verbena bonariensis offers continuous blooms from July until the first frost. Its bright purple flowers provide a long-lasting burst of color, helping to keep your garden vibrant late into the season.
Wildlife Magnet: If you want to attract pollinators to your garden, this plant is a must-have. Its nectar-rich flowers are irresistible to bees, butterflies, and hoverflies, making it a favorite in wildlife gardens.
Architectural Interest: The tall, thin stems of Verbena bonariensis allow you to plant it among shorter plants without overwhelming them. Its openness adds structure without bulk, creating a vertical accent that brings a layered, architectural look to borders and flower beds.

A Closer Look at the Plant:

Botanical name: Verbena bonariensis
Common names: Purpletop vervain, Argentinian vervain, Tall verbena
Family: Verbenaceae
Height: 120-180 cm (4-6 feet)
Spread: 45-60 cm (1.5-2 feet)
Flower color: Purple/lavender
Bloom time: July to October (until first frost)
Hardiness: Hardy in the UK, down to -10°C (RHS Hardiness rating H4)

Growing Verbena bonariensis in UK Gardens

Despite its somewhat exotic look, Verbena bonariensis is surprisingly easy to grow in UK gardens, and it’s a hardy perennial that comes back year after year. Here’s everything you need to know about successfully cultivating this beautiful perennial.

1. Choosing the Right Location

Verbena bonariensis thrives in sunny, well-drained locations, so pick a spot in your garden where it will receive full sunlight for at least 6 hours a day. This perennial loves warmth and sun but can handle the temperamental UK climate quite well.

Sunlight requirements: Full sun, though it can tolerate light shade.
Soil preferences: Well-drained soil is key. It will tolerate a variety of soil types, from loamy to sandy, as long as the drainage is good. It’s not fond of waterlogged soils, so avoid planting it in boggy areas of your garden.

Tip: If you have heavy clay soil, consider adding grit or sand to improve drainage, or plant Verbena bonariensis in raised beds or containers.

2. Planting Verbena bonariensis

You can plant Verbena bonariensis as a young plant or start it from seed. While growing from seed requires a bit of patience, this method allows you to propagate many plants at once for a large garden display.

From seed: Sow Verbena bonariensis seeds indoors in early spring (March-April) or direct sow them outside after the last frost in May. Seeds can be slow to germinate, so don’t be discouraged if they take a few weeks to show signs of life. Once seedlings have two sets of true leaves, they can be transplanted into their final position.
From plants: If you’re planting young nursery plants, space them about 45 cm apart to give them room to spread. Dig a hole slightly larger than the root ball, place the plant in the hole, backfill with soil, and water well.

Tip: Verbena bonariensis is often described as “self-seeding,” meaning it can propagate itself by dropping seeds that sprout the following year. This can lead to delightful surprises in your garden, as new plants appear in unexpected places.

3. Watering and Care

Verbena bonariensis is relatively low-maintenance once established, making it perfect for busy gardeners. Here’s how to care for it throughout the growing season:

Watering: This perennial is drought-tolerant once it’s established. Water young plants regularly until they are settled in, then reduce watering to occasional deep soaks during dry spells.
Fertilizing: Verbena bonariensis doesn’t need much in the way of fertilizers. In fact, too much nitrogen can lead to leggy growth and fewer flowers. A light application of a balanced fertilizer in early spring is sufficient.
Deadheading: To encourage continuous blooming, regularly deadhead the spent flowers. This not only keeps the plant looking tidy but also prevents it from going to seed too early, prolonging the flowering period.

Tip: If you want to encourage self-seeding, leave some flowers to go to seed in the late autumn.

4. Winter Care

While Verbena bonariensis is hardy in most parts of the UK, it may struggle in colder areas with harsh winters. In these regions, you can protect the plant by applying a thick layer of mulch around the base in autumn, which helps insulate the roots from frost.

Pruning: In early spring, after the worst of the frosts have passed, cut back the old stems to ground level to make way for new growth. This rejuvenates the plant and encourages strong, healthy shoots for the new season.

Pairing Verbena bonariensis with Other Plants

One of the best things about Verbena bonariensis is its versatility in garden design. Thanks to its tall, airy structure, it pairs beautifully with a wide range of other plants. Whether you’re creating a traditional cottage garden, a modern mixed border, or a wildlife-friendly haven, this perennial fits right in.

Ideal Planting Companions:

Grasses: Ornamental grasses like Stipa tenuissima or Miscanthus make excellent companions for Verbena bonariensis. The soft, feathery texture of grasses complements the tall, upright form of the verbena, creating a dynamic interplay of height and texture.
Echinacea and Rudbeckia: Both of these sturdy, daisy-like perennials thrive in similar conditions to Verbena bonariensis and bloom at the same time. The warm, sunny colors of Rudbeckia and Echinacea (often in shades of yellow, orange, and pink) contrast beautifully with the cool purple hues of Verbena bonariensis.
Lavender and Salvia: For a monochromatic color scheme, pair Verbena bonariensis with lavender or salvia. The silvery foliage of Lavandula and the upright spires of Salvia nemorosa echo the ethereal quality of verbena, creating a calming and cohesive display.
Roses: Plant Verbena bonariensis around rose bushes to provide a natural, loose framework that offsets the more solid structure of the roses. The slender stems of verbena won’t compete with the roses for space or light but will instead weave through the roses to add height and movement.
Wildflowers: Verbena bonariensis can also be incorporated into wildflower meadows or more naturalistic planting schemes. It adds height and color without overwhelming smaller flowers like Oxeye daisies (Leucanthemum vulgare) or Field Scabious (Knautia arvensis).

Tip: Avoid pairing Verbena bonariensis with short, dense perennials that won’t benefit from its height. Instead, think of it as an accent plant, weaving between other species to add interest and diversity.

The Benefits of Growing Verbena bonariensis

1. Attracting Wildlife

If you’re looking to create a wildlife-friendly garden, Verbena bonariensis is an essential plant. Its nectar-rich flowers are a magnet for pollinators, including bees, butterflies, and hoverflies. In fact, it’s one of the best plants you can grow for attracting butterflies, such as the Painted Lady and the Peacock butterfly.

Verbena bonariensis also provides perching spots for birds. In the late summer and autumn, birds such as finches will often use the tall stems to perch while they feed on seeds or insects in the garden. By leaving some flowers to go to seed, you can also provide food for birds in the colder months.

Tip: Plant Verbena bonariensis near a seating area or along pathways so you can enjoy watching the wildlife it attracts up close.

2. Low-Maintenance Gardening

Verbena bonariensis is a dream for gardeners who want a beautiful, impactful garden without constant maintenance. Its drought tolerance and minimal feeding requirements mean you can largely leave it to its own devices once it’s established. Even better, it tends to be pest-resistant, meaning you won’t have to worry about aphids, slugs, or other common garden nuisances damaging your plants.

3. Versatility in Garden Design

Thanks to its height and structure, Verbena bonariensis works in a wide range of garden styles. Whether you’re aiming for a classic cottage garden, a contemporary minimalist border, or a wilder, naturalistic design, this perennial fits in beautifully. Its openness also allows it to blend with other plants without crowding them out, giving you plenty of design flexibility.

4. Long-Lasting Flowers

One of the biggest advantages of Verbena bonariensis is its long blooming period. While many perennials have a short flowering window, this plant will keep flowering from midsummer well into autumn. This means you can enjoy its vibrant color and airy structure in your garden for months on end, with minimal deadheading or upkeep required.

Time to Get Growing!

In a world where the most popular perennials often steal the spotlight, Verbena bonariensis stands out as a tall, unusual, and utterly captivating addition to any UK garden. Its long-lasting blooms, wildlife appeal, and architectural structure make it an essential plant for anyone looking to add something special to their outdoor space.

Whether you’re an experienced gardener or just getting started, Verbena bonariensis is a plant that rewards you with beauty and simplicity. So, if you’re ready to try something a little different in your garden this year, why not give this South American stunner a go? Your garden—and the pollinators—will thank you for it!

Let us know! Are you growing Verbena bonariensis in your garden? Share your experiences, tips, and favorite companion plants in the comments below! Let’s celebrate this beautiful perennial together.