Plant Database

Other Names:  Giant Seakale

Description:

A striking plant with huge glossy leaves that are deeply lobed, forming a mound; clouds of tiny star shaped flowers are held above on tall stalks in early to mid-summer; great for a large border; not easily divided but seedlings may appear at base

Ornamental Features

Heartleaf Colewort features bold spikes of white star-shaped flowers rising above the foliage in early summer. Its glossy heart-shaped leaves emerge green in spring, turning dark green in colour throughout the season.

Landscape Attributes

Heartleaf Colewort 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 be cut back in late fall in preparation for winter. It is a good choice for attracting butterflies to your yard. Gardeners should be aware of the following characteristic(s) that may warrant special consideration;

• Self-Seeding

Heartleaf Colewort is recommended for the following landscape applications;

• Accent
• Mass Planting
• General Garden Use
• Container Planting

Planting & Growing

Heartleaf Colewort will grow to be about 24 inches tall at maturity extending to 5 feet tall with the flowers, with a spread of 4 feet. It has a low canopy with a typical clearance of 1 foot from the ground. 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 somewhat tolerant of urban pollution, and will benefit from being planted in a relatively sheltered location. This species is not originally from North America.

Heartleaf Colewort is a fine choice for the garden, but it is also a good selection for planting in outdoor pots and containers. With its upright habit of growth, it is best suited for use as a 'thriller' in the 'spiller-thriller-filler' container combination; plant it near the center of the pot, surrounded by smaller plants and those that spill over the edges. It is even sizeable enough that it can be grown alone in a suitable container. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.