GLENCOE, Ill.  (Jan. 24, 2006) – The Chicago Botanic Garden is releasing results
of a six-year study of Stachys in its 27^th issue of Plant Evaluation Notes: A Comparative Study of Cultivated Stachys.

The Chicago Botanic Garden evaluated 22 taxa of Stachys from 1998 through 2004 to identify outstanding selections through an assessment of their ornamental traits, disease and pest resistance, cultural adaptability and winter hardiness. Cultivated Stachys are informally divided into two groups based on floral display, foliage and plant habit. One group includes S. byzantina and S. thirkei, which have silvery to gray-green, woolly leaves in a sprawling mat of rosettes and small or no flowers. The other group, commonly known as betony, includes S. macrantha, S. officinalis and S. monieri, which produce showy spikes of flowers above bushy mounds of rugose (wrinkled) green leaves.

Stachys are generally easy-to-grow perennials for moist, well-drained soils in full-sun to light shade. Lamb's ears are great for edging beds and softening walks, or as a groundcover, or accent in the border and rock garden. Betonies bring a casual formality to the border, herb garden, cottage garden or meadow.

The majority of taxa received four-star good ratings, with only one taxon receiving poor marks. Stachys palustris was eliminated before the trial ended because its aggressive/weedy habit was determined undesirable in a cultivated setting.

Stachys monieri 'Hummelo' received the highest rating in the trial based on strong flower production, plant health, habit quality and winter hardiness.  Its dark green leaves remained healthy and ornamental throughout the summer. Its violet flowers were ½-inch in length with 80 to 100 percent coverage from mid-July to early August. Of the silvery-leaved taxa, S. byzantina, S. byzantina 'Big Ears,' S. byzantina 'Cotton Boll' S. byzantina 'Silver Carpet' and S. byzantina 'Wave Hill' all received four stars.

There was no consistent pattern of winter injury noted in the trial, except for Stachys byzantina 'Primrose Heron,' which suffered crown damage each winter. Plant health was generally good for the taxa, but occasional health issues included minor chlorosis and crown meltout caused by excessive moisture. 
           
Phlomis, an uncommon plant in midwestern gardens and a relative of Stachys, was also evaluated. Three Phlomis taxa were successfully grown in full-sun trials from 1997 through 2001. Phlomis russeliana (Jerusalem sage) featured abundant 1-inch long, hooded, butter yellow flowers throughout June. Phlomis tuberosa was similar in habit, but with rugose green leaves and lavender-pink flowers borne in densely whorled clusters.

Phlomis russeliana should be grown in a warm, protected site for optimum growth and it is intolerant of wet or poorly drained soils. Phlomis tuberosa is more adaptable to average garden conditions and benefits from deadheading.

The Chicago Botanic Garden's Plant Evaluation Notes provide the latest information on plants suited to the midwestern climate and growing conditions. Cost is $3 per copy. To obtain Issue 27, A Comparative Study of Cultivated Stachys, write to the following address:

Plant Evaluation Notes

c/o Richard Hawke

Chicago Botanic Garden

1000 Lake Cook Road

Glencoe, IL  60022

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Editors, please note: The Chicago Botanic Garden’s newsroom is online at www.chicagobotanic.org/pr. For digital images, contact Julie McCaffrey at (847) 835-8213 or at jmccaffrey@chicagobotanic.org.

The Chicago Botanic Garden is a 385-acre living plant museum featuring 23 distinct display gardens surrounded by lakes, as well as a prairie and woodlands. With events, programs and activities for all ages, the Garden is open every day of the year, except Dec. 25. Admission is free; select event fees apply. Parking is $15; free for members. On Tuesdays, senior citizens age 62 and older pay just $7 for parking. The Garden is located at 1000 Lake Cook Road in Glencoe, Ill. Visit www.chicagobotanic.org, or call (847) 835-5440 for seasonal hours, images of the Garden and commuter transportation information.

 The Chicago Botanic Garden is owned by the Forest Preserve District of Cook County and managed by the Chicago Horticultural Society. It opened to the public in 1972 and is home to the Joseph Regenstein, Jr. School of the Chicago Botanic Garden, offering a broad array of adult classes in plant science, landscape design and gardening arts. The Center for Teaching and Learning brings the wonder of nature and plants to children, teens and teachers. Horticultural Therapy and Community Gardening provide nationally recognized community outreach and service programs. Through the Institutes of Plant Conservation and Ornamental Plant Research, Garden scientists work on plant conservation, research and environmental initiatives that have global impact. The Chicago Botanic Garden is accredited by the American Association of Museums and is a member of the American Public Gardens Association (APGA). In 2006, the Chicago Botanic Garden received the Award for Garden Excellence, given yearly by the APGA and Horticulture magazine to a public garden that exemplifies the highest standards of horticultural practices and has shown a commitment to supporting and demonstrating best gardening practices.