VANDERMEER
PLANT LIBRARY
Find the perfect plant for your space by browsing through this extensive selection that we typically carry every year.
This library is for information purposes only.
Blacknight Hollyhock
Alcea rosea 'Blacknight'
Plant Height: 3 feet
Flower Height: 6 feet
Spread: 24 inches
Sunlight:
Hardiness Zone: 3a
Other Names: Althaea rosea
Group/Class: Spotlight™ Series
Brand: Walter's Gardens
Description:
Featuring deep black-purple flowers on towering spikes in midsummer; tolerant to the natural toxin formed by the roots of Black Walnut; selections from this series are truly perennial; plant in full sun for better growth
Ornamental Features
Blacknight Hollyhock features bold spikes of black round flowers with white eyes and deep purple streaks rising above the foliage from mid summer to early fall. The flowers are excellent for cutting. Its large tomentose round leaves remain grayish green in colour throughout the season.
Landscape Attributes
Blacknight Hollyhock is an herbaceous perennial with a rigidly upright and towering form. Its relatively coarse texture can be used to stand it apart from other garden plants with finer foliage.
This plant will require occasional maintenance and upkeep, and should only be pruned after flowering to avoid removing any of the current season's flowers. It is a good choice for attracting bees to your yard, but is not particularly attractive to deer who tend to leave it alone in favor of tastier treats. Gardeners should be aware of the following characteristic(s) that may warrant special consideration;
- Disease
- Self-Seeding
Blacknight Hollyhock is recommended for the following landscape applications;
- Vertical Accent
- Mass Planting
- General Garden Use
Planting & Growing
Blacknight Hollyhock will grow to be about 3 feet tall at maturity extending to 6 feet tall with the flowers, with a spread of 24 inches. The flower stalks can be weak and so it may require staking in exposed sites or excessively rich soils. It grows at a fast rate, and under ideal conditions can be expected to live for approximately 10 years. As an herbaceous perennial, this plant will usually die back to the crown each winter, and will regrow from the base each spring. Be careful not to disturb the crown in late winter when it may not be readily seen!
This plant should only be grown in full sunlight. It does best in average to evenly moist conditions, but will not tolerate standing water. It is not particular as to soil type or pH. It is highly tolerant of urban pollution and will even thrive in inner city environments. This is a selected variety of a species not originally from North America.