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Gardening in the Rainy Zone.
Penstemon 'Dark Towers'
TALL BEARD TONGUE
Sunset zones: 1-11, 14-24.
USDA zones: 3-8.
Heat zones: 8-1.
Height: 30 inches (76 cm).
Width: 33 inches (84 cm).
Spikes of tubular, two-lipped, soft lavendar-pink flowers with white throat.
Narrow, glossy, dark burgundy leaves.
Well-drained, average soil.
Fertilize in spring with a complete organic fertilizer.
Divide in Spring.
Soft-wood cuttings in June.
Semi-ripe cuttings midsummer.
When flowers fade trim flower stalks to tidy up the plant.
Pests and Diseases:
Protect from slugs when young.
Rainy Side Notes
You know this has to be one tough plant, considering it originated at the University of Nebraska, and was bred by Penstemon expert Dale Lindgren, who also developed P. ‘Husker Red’. In 2008, Terra Nova Nurseries introduced P. ‘Dark Towers’ to the trade. I’ve grown both and believe the latter is a remarkable improvement over the former.
When it sends up its spikes of flowers, this perennial is three feet tall and stately; the dark foliage stands out in a perennial sea-of-green border. However, it also begs a closer look with an eye for detail, where you can notice the fine silvery hairs contrasting the dark stems and leaves. No matter which way you look at the flowers, each view provides a different perspective, from the side view’s come-hither look of a fully open flower, the view down its hairy throat, or its tight-fisted looking bud.
Do not hide this in the back of the border, place it where you can view the glossy, dark burgundy leaves that hold their color all season long. In my garden, it grows in a mulched raised bed where it’s rarely watered and never fertilized. It tends to be floppy, so I stake it.
Penstemon ‘Dark Towers’ is a deer and rabbit resistant plant; but the hummingbirds and butterflies love it.
Photographed in author's garden.
Perennials indexed by botanical names. Click on corresponding letter below.