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Penstemon rupicola
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New article for Trees and Shrubs Online.
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'Penstemon rupicola' from the website Trees and Shrubs Online (treesandshrubsonline.
Synonyms
- Penstemon newberryi var. rupicola Piper
This species is near to P. newberryi and was originally described as a variety of it, from a specimen collected on Mount Rainier. It differs in its prostrate, creeping habit; in its markedly glaucous, thick leaves, which usually have short, inconspicuous hairs on the midrib and main veins; in the fewer-flowered inflorescence; and in the more ventricose shape of the corolla. In the cultivated plant the colour of the flowers is pinker than in P. newberryi. Bot. Mag., t. 8660.
P. rupicola has a limited distribution from Washington to N. California. It was introduced to cultivation around 1910 and was distributed by Clarence Elliott’s Six Hills nursery as “P. davidsonii”, a name that belongs to a different, though related, species. It is hardy in a sunny place in well-drained soil.The hybrid ‘Six Hills’ was the result of a cross between P. rupicola and P. eriantherus (P. cristatus), the second parent being an almost herbaceous species not treated here.
