Plant Guide

Other Names:  Lyreleaf Sage

Ornamental Features

Purple Knockout Sage's attractive glossy oval leaves emerge light green in spring, turning deep purple in colour with curious burgundy undersides on a plant with a low base above which the flowers rise. As an added bonus, the foliage turns a gorgeous red in the fall. It features delicate spikes of burgundy flowers rising above the foliage from late spring to mid summer. The deep purple stems can be quite attractive.

Landscape Attributes

Purple Knockout Sage is an herbaceous perennial with tall flower stalks held atop a low mound of foliage. Its medium texture blends into the garden, but can always be balanced by a couple of finer or coarser plants for an effective composition.

This plant will require occasional maintenance and upkeep, and is best cleaned up in early spring before it resumes active growth for the season. It is a good choice for attracting bees, butterflies and hummingbirds 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;

• Self-Seeding

Purple Knockout Sage is recommended for the following landscape applications;

• Mass Planting
• Border Edging
• General Garden Use
• Groundcover
• Container Planting

Planting & Growing

Purple Knockout Sage will grow to be about 8 inches tall at maturity extending to 18 inches tall with the flowers, with a spread of 12 inches. When grown in masses or used as a bedding plant, individual plants should be spaced approximately 10 inches apart. Its foliage tends to remain low and dense right to the ground. It grows at a fast rate, and under ideal conditions can be expected to live for approximately 5 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 is an amazingly adaptable plant, tolerating both dry conditions and even some standing water. It is considered to be drought-tolerant, and thus makes an ideal choice for a low-water garden or xeriscape application. It is not particular as to soil pH, but grows best in clay soils. It is somewhat tolerant of urban pollution. Consider covering it with a thick layer of mulch in winter to protect it in exposed locations or colder microclimates. This is a selection of a native North American species. It can be propagated by division; however, as a cultivated variety, be aware that it may be subject to certain restrictions or prohibitions on propagation.

Purple Knockout Sage is a fine choice for the garden, but it is also a good selection for planting in outdoor pots and containers. It is often used as a 'filler' in the 'spiller-thriller-filler' container combination, providing a mass of flowers and foliage against which the larger thriller plants stand out. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden. Be aware that in our climate, this plant may be too tender to survive the winter if left outdoors in a container. Contact our experts for more information on how to protect it over the winter months.