Ageratina altissima 'Chocolate' (Ageratina altissima 'Chocolate')
Ageratina altissima 'Chocolate' offers striking chocolate-tinted foliage and late-season white flowers. Easy care perennial for moist, shady zones 4-8.
Complete Plant Information
Overview
Ageratina altissima ‘Chocolate’ is a distinctive herbaceous perennial valued for its unique deep-hued foliage that contrasts beautifully with its late-season blooms. This cultivar brings rich color interest to the garden later in the year when many other plants are winding down. It fits seamlessly into woodland or rain garden settings, providing vertical structure without demanding heavy attention.
This plant thrives in conditions ranging from full sun to partial shade, showing superior shade tolerance compared to many related species. It prefers average, medium to wet, well-drained soils but is adaptable, even handling moderately dry conditions reasonably well once established. Gardeners appreciate its low maintenance needs and aggressive, yet manageable, spreading habit via rhizomes.
While technically a cultivar, Ageratina altissima ‘Chocolate’ offers native aesthetics combined with unique ornamental value. Its fluffy white flower clusters, appearing from late summer into autumn, attract beneficial insects while the dark, chocolate-tinted leaves provide lasting visual appeal throughout the growing season.
Fast Facts
- Plant Family: Asteraceae
- Plant Type: Herbaceous perennial
- Hardiness Zones: USDA Zones 4-8
- Size at Maturity:
- Height: 3-5 ft
- Spread: 2-3 ft
- Bloom Time: September to October
- Bloom Description: White
- Sun Exposure: Full sun to part shade
- Water Needs: Medium to wet
- Maintenance Level: Low
How to Grow
Plant Ageratina altissima ‘Chocolate’ in the spring or fall, ensuring the soil is moist and well-drained for the best establishment. While these plants tolerate drier soil, they perform optimally in rich, humusy soils, especially if sited in partial shade. Good drainage is crucial to prevent root issues, even though they tolerate wet conditions readily, making them excellent for rain gardens.
Maintenance for this perennial is generally low. Water regularly until the plant is established, especially during dry spells, as they prefer medium to wet soil moisture levels. Fertilization is rarely necessary if the native soil structure is even moderately rich.
To keep the plant tidy and avoid prolific self-seeding, it is recommended to deadhead the fluffy white flower heads once blooming concludes in the fall. Be aware that Ageratina altissima ‘Chocolate’ spreads reliably by both rhizomes and seed; if you do not wish for it to naturalize aggressively, consistent deadheading is essential. Note that ‘Chocolate’ will not come true to type if propagated via seed.
Landscape Uses
Ageratina altissima ‘Chocolate’ excels in creating naturalistic plantings. Its suitability for naturalizing makes it ideal for large woodland edges or wild gardens where it can fill in space effectively. Furthermore, its requirement for medium to wet soil positions it perfectly within rain garden designs, helping to manage stormwater runoff while adding textural interest.
This perennial should be considered for areas needing late-season vertical interest, such as cottage gardens or shady corners along borders. Given its rhizomatous spread, plant it where space allows, or use containment measures if planting near smaller, less vigorous selections. The dark foliage provides a superb backdrop for lighter-colored late-blooming perennials.
Standout Features
Flower Qualities
- Showy
Noteworthy Characteristics
Ageratina altissima commonly called white snakeroot, is native to woodland areas in the Eastern United States. It is common throughout Missouri where it typically occurs in rich or rocky woods, thickets, wood margins and rocky areas (Steyermark). It features small fluffy bright white flowers (composites with rays absent) arranged in loose, flattened clusters (corymbs to 3-4” across) atop smooth stems typically rising 3-5’ tall. Blooms from late summer to frost. This is a somewhat weedy perennial that can spread aggressively by rhizomes and self-seeding. Long-stalked, sharp-toothed, taper-pointed, lance-shaped to elliptic-oval, nettle-like, dark green leaves (3-6” long) are paired along the stems. Native Americans reportedly used a decoction of the roots as a remedy for snakebite, hence the common name. Settlers who drank milk from cows that fed on this plant often developed the disease called milk sickness. This plant is synonymous with Eupatorium rugosum.Specific epithet means tall or highest.‘Chocolate’ features small white fluffy flowers atop shiny purple stems typically rising 3-5’ tall. Sharp-toothed, lance-shaped to elliptic-oblong leaves (4-7” long) are chocolate-tinted, thus giving rise to the cultivar name. An exclusive introduction of the Mt. Cuba Center of Greenville, Delaware.
Tolerances
- Deer
Potential Problems
Ageratina altissima ‘Chocolate’ boasts a robust profile with no consistently serious insect or disease issues that typically plague gardeners. However, be vigilant for occasional cosmetic damage from leaf miners or flea beetles attacking the foliage during warm weather. The primary management concern revolves around its vigorous growth habit; this plant self-seeds readily and spreads rapidly via rhizomes in optimal growing conditions, requiring proactive deadheading or division to maintain boundaries.
Frequently Asked Questions
What hardiness zones is Ageratina altissima ‘Chocolate’ suitable for?
Ageratina altissima ‘Chocolate’ is most reliably hardy in USDA Zones 4 through 8.
How large does Ageratina altissima ‘Chocolate’ grow?
This perennial typically reaches a height between 3 to 5 feet tall and spreads to 2 to 3 feet wide.
What sun exposure does Ageratina altissima ‘Chocolate’ need?
It performs well in locations receiving full sun or part shade, adapting nicely to various light levels.
When does Ageratina altissima ‘Chocolate’ bloom?
The plant produces its white, fluffy blooms primarily from September into October.
Conclusion
Ageratina altissima ‘Chocolate’ is a valuable, low-maintenance addition for gardeners seeking late-season structure and unique foliage texture. The contrasting chocolate stems and leaves provide excellent year-round depth, complemented by its late white flower display. Ensure you check that your site falls within USDA Zones 4-8 and plan accordingly for its spreading nature before planting this superb cultivar.
Propagation Tips
Division is the most reliable method for multiplying Ageratina altissima ‘Chocolate’ while maintaining the desired characteristics of the cultivar. The best time for dividing is typically in early spring just as new growth begins to emerge, or in the early fall before the ground freezes hard. Dig carefully around the clump to sever the spreading rhizomes, ensuring each new division has a significant section of root mass attached.
While the species can be grown easily from seed, remember that the ‘Chocolate’ cultivar will not breed true from seed, meaning seedlings will revert toward the standard white snakeroot characteristics. Therefore, if seed propagation is attempted, treat it as a way to collect genetic diversity rather than propagation of the specific purple-stemmed type.
Wildlife Benefits
The late bloom time of this plant, stretching into September and October, provides a crucial late-season nectar source for pollinators preparing for winter migration or dormancy. The small, fluffy white flowers are highly attractive to various small native bees and beneficial wasps seeking energy resources nearing the end of the season.
Planting Ageratina altissima ‘Chocolate’ near naturalized areas or along woodland borders supports a more continuous ecological corridor for local fauna. While the species has historical toxicity concerns regarding livestock (milk sickness), native bees and non-livestock wildlife generally utilize the nectar and pollen safely.
