The Verbena plant genus encompasses over 250 different types of plants that are annual and perennial.
Pure species of this genus, such as Verbena rigida (Slender Vervain) are less frequently seen in gardens, typically only grown by gardeners who are fans of traditional plants.
Verbena rigida is a low-spreading type of verbena that's great for covering the ground in your garden. There are numerous cultivars available, such as "Stantos" and "Polaris,".
These tend to grow fine in USDA zones 7 to 9. Mixed breed verbenas, or hybrids, are really tough plants in USDA zones 8 to 11. But, you can grow them as annuals in any zone.
Verbena is usually a short plant that grows out rather than up. It has dark green leaves with edges that look like they have teeth. It produces groups of colorful flowers from spring until fall that will make any gardener happy.
How to Grow Verbena Rigida
Growing Verbena rigida is pretty straightforward. These plants like lots of sun, and a soil that drains water well. They don't do well if the soil is too crowded or soggy, as they can get root rot.
Make sure to give your plants enough room to grow, so that air can move around them. The exact space you need depends on the type of you are growing. Cut the plants back once or twice a year to encourage them to grow, and to produce more flowers.
Avoid planting in shady areas, as this slows down growth and flowering. These plants require at least six hours of sunlight each day, witheight to ten hours being even better for blooming.
Verbena rigida plants prefer a loamy soil with a pH balance of between 5.8 and 7.2. That said, they are not too picky about soil pH level, so as long as it drains water well. They do not do well in clay-like soil, as this retains waterand can lead to root rot.
Water your Verbena rigida to keep it moist until it has settled into your garden.
Once your plants have matured, they typically need about one to two inches of water per week. They can readily handle a few weeks without water if conditions are dry. Over watering can lead to botrytis blight, whilst under-watering may result in attracting spider mites.
If you plant Verbena rigida as an annual, it will do well in most climates, but it might struggle in the very hot parts of summer.
When grown as perennials in zones 8 to 11, hybrid verbenas are sturdy. They do not need lots of food, but they do enjoy a bit of slow-release, balanced fertilizer to help them flower better.
Quick Verbena rigida Growing and Care Guide
Scientific Name: Verbena rigida
Common Name(s): Slender Vervain, Tuberous Vervain, Stiff Verbana
Growing Zone (USA / UK Hardiness): USDA Zones: 7-10 RHS Hardiness Rating: H4 (-10 to -5°C)
Best Used For / Garden Location: Flower beds, borders, rock gardens, containers.
Plant Details
Life Cycle / Plant Type: Herbaceous perennial
Plant Height: 1-1.5 feet (30-45 cm)
Plant Spread: 1.5-2 feet (45-60 cm)
Blooms: Summer through fall
Flower Details: Small, tubular, bright purple flowers in clusters
Leaf Foliage: Narrow, toothed, dark green leaves
Fruit: N/A
Growing Conditions and Location
Best Light Conditions: Full sun
Suitable Soil Types: Well-drained, average to sandy soil
Sowing / planting: Plant young plants in spring.
Germination time: 14-28 days at 70°F (21°C)
Propagation: By seed in spring or by cuttings in early summer.
Plant Care: Deadhead to prolong flowering.
Growing in pots and containers: Suitable for containers.
Growing as a House plant: Not typically grown as a houseplant.
Further Information
Miscellaneous: Attracts butterflies. Drought and heat tolerant.
Pests and diseases: Susceptible to powdery mildew, downy mildew, and rust.
Common Cultivars / Varieties: 'Polaris' (pure white flowers), 'Santos' (dark purple flowers)
Family: Verbenaceae, the Verbena family.
Native: South America.
References and Further Reading: Royal Horticultural Society; NC State Extension; Penn State plant identification.
Common Questions
Does Verbena Rigida make a good garden or landscaping plant?
Verbena rigida, or Slender Vervain, makes a great garden plant due to its long blooming period and attractive, purple flowers. It works well in borders, containers, or as a ground cover.
Is Verbena rigida a fragrant plant?
Yes, Verbena rigida is a fragrant plant. It has a sweet, mildly lemony scent that can be a nice addition to a garden or bouquet.
What is the perfect location to grow Slender Vervain?
Slender Vervain prefers a location with full sun and well-drained soil. It's drought-tolerant once established, making it a good choice for xeriscaping or sunny borders.
Is Verbena rigida invasive?
Verbena rigida is not considered invasive in the USA, but has become naturalized in southeastern North Carolina through to Florida. It has become invasive in Australian wwodlands and graslands, and is also though invasive in South Africa. It is a vigorous grower, spreading rapidly from its rhizomes, and can spread through self-seeding. So some maintenance may be required to keep it contained.
How do I remove it from my garden?
To remove Verbena rigida, pull up the plants, ensuring to remove as many roots as possible. Sieve soil to remove traces of rhizomes. Regularly remove spent flowers to prevent self-seeding, and unwanted spread.
Summary
Slender Vervain is a drought-tolerant perennial with vibrant purple flowers. Plant in well-drained soil in full sun. Water deeply but infrequently, allowing the soil to dry out between watering.
I hope that you have enjoyed reading this guide on how to grow Verbena rigida. You may also enjoy the following growing guides: How to grow Verbena bonariensis, Lantana montevidensis, and Cenolophium plants in the garden.
