Purpletop Vervain: A Delicate Beauty for Your Garden
Meet purpletop vervain (Verbena incompta), a charming plant that brings an airy, naturalistic feel to gardens across much of North America. With its delicate purple flower clusters dancing atop slender stems, this South American native has found a comfortable home in landscapes from coast to coast.
What Exactly Is Purpletop Vervain?
Purpletop vervain is a non-woody flowering plant that can behave as an annual, biennial, or perennial depending on your climate and growing conditions. Originally from South America, this adaptable species has established itself across a wide range of North American regions, from the sunny Southwest to the humid Southeast.
You might also see this plant listed under its synonyms Verbena bonariensis in older gardening references, though botanists have since clarified the proper identification.
Where Does It Grow?
This versatile plant has spread far from its South American origins and now grows in an impressive list of locations including Alabama, Arizona, Arkansas, California, Florida, Georgia, Hawaii, Illinois, Louisiana, Massachusetts, Mississippi, New Jersey, New York, North Carolina, Oklahoma, Oregon, South Carolina, Tennessee, Texas, Virginia, and Puerto Rico. It’s even made its way into parts of Canada, specifically Ontario and Quebec.
Should You Plant Purpletop Vervain?
The answer depends on what you’re looking for in your garden. Here are some reasons you might want to consider it:
- Creates a soft, naturalistic appearance in informal garden settings
- Attracts butterflies, bees, and other beneficial pollinators
- Thrives in well-drained soils and tolerates drought once established
- Self-seeds readily, providing ongoing garden interest
- Works well in cottage gardens, meadow plantings, and pollinator gardens
However, since purpletop vervain isn’t native to North America, you might want to consider native alternatives that provide similar benefits while supporting local ecosystems. Native vervain species like blue vervain (Verbena hastata) or Brazilian vervain alternatives native to your region could be excellent substitutes.
Growing Conditions and Care
Purpletop vervain is refreshingly low-maintenance once you understand its preferences:
- Sunlight: Full sun for best flowering
- Soil: Well-drained soil; adaptable to various soil types
- Water: Drought tolerant once established; avoid overwatering
- Hardiness: Zones 7-10 (grows as annual in colder areas)
According to wetland indicators, this plant typically prefers non-wetland conditions but can occasionally tolerate some moisture, making it quite adaptable to different garden situations.
Planting and Care Tips
Getting started with purpletop vervain is straightforward:
- Plant in spring after the last frost date
- Space plants adequately as they can self-seed and spread
- Deadhead spent flowers if you want to prevent excessive self-seeding
- Allow some flowers to go to seed if you want natural reseeding
- Minimal fertilization needed; too much can reduce flowering
- Cut back in late fall or early spring in perennial zones
The Bottom Line
Purpletop vervain offers gardeners an easy-care option for adding delicate purple blooms and pollinator appeal to naturalistic landscapes. While it’s not native to North America, it’s not considered invasive either, making it a neutral choice for gardeners who appreciate its aesthetic qualities. Just remember to consider native alternatives first – your local ecosystem will thank you, and you’ll likely find equally beautiful options that are perfectly adapted to your specific region.
Whether you choose purpletop vervain or a native alternative, you’ll be adding valuable pollinator habitat and natural beauty to your garden space.
