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Penstemon isophyllus
Credits
Article from Bean's Trees and Shrubs Hardy in the British Isles
Recommended citation
'Penstemon isophyllus' from the website Trees and Shrubs Online (treesandshrubsonline.
A semi-shrubby plant of bushy habit, 2 to 3 or more ft high; young shoots densely leafy and very minutely downy. Leaves opposite, elliptic-ovate, 1 to 21⁄2 in. long, 1⁄3 to 1 in. wide, pointed or blunt, rather fleshy, dark green, minutely warted and glaucous beneath, sessile or scarcely stalked. Flowers scarlet-crimson with pale lines in the throat, borne on loose, erect racemes 8 to 15 in. long, corolla tubular, 11⁄2 to 13⁄4 in. long, 2⁄3 to 1 in. across, two-lipped, the upper lip two-lobed, the lower one three-lobed, the lobes rounded; fertile stamens four, white, two attached to the bottom of the corolla-tube, the other pair amalgamated with the corolla for the lower half-inch. The flowering season is late summer and autumn. Bot. Mag., t. 9482.
Native of Mexico, introduced in 1908. It is a plant of great beauty but not quite hardy, although it may survive several mild winters in a sheltered position. If merely cut back to the base it will spring up again. It is an admirable plant for the milder parts.