Hosta rupifraga (T. Nakai 1930/AHS 1993)
|Hosta Library species file||Hosta rupifraga|
|Origin||Japan, Hachijo Island, one of the Izu Islands. See Map.|
|Habitat||Inside the caldera (crater) of the volcano Hachijo-Fuji, ponds and marshy grasslands are formed. It is only in the cooler climate of the mountain top, mostly among tall grasses, that H. rupifraga exists. Its natural, allopatric population is limited to the rim, elevation 2,500 feet (845 meters) and just below.|
|Japanese name||Hachijo Giboshi = the Hosta from Hachijo Island|
|Plant||25–30 cm diameter x 15–20 cm high (10–12 x 6–8").|
Petiole 25–7.5 cm (1–3"), rigid, blunt on back, not keeled,
Leaf 12.5–15 cm x 10–12.5 cm wide (5–6 x 4–5"), erect and in line with petiole, leathery, elongated ovate to ovate-cordate, transition tight and contracted, very acuminate tip, undulate in the margin when mature, smooth surface, dark green above, lighter green below.
6–8 pairs of veins, widely spaced, projected, glabrous below.
Scape 25–30 cm long (10–12"), obliquely arching, smooth,
round, sea-green, slightly pruinose, permanently
purple-dotted in lower half.
Sterile bracts 3–5; fertile bracts 2 cm, navicular, thick, densely imbricated, whitish green, tinted purple in margin, withering, falling away during anthesis.
Raceme short, densely arranged, 8–12 flowers.
Flowers 4 cm long and 2 cm broad (1.7 x 0.8"), purple-striped inside, thin narrow tube, perianth expanding, lobes straightly spreading, bell-shaped, pedicels 1.2 cm (0.5"), abruptly nodding, stamens shorter than the perianth.
Anthers bi-color purple-yellow.
|Suitable for containers|
H. rupifraga 'Tetra' is an incorrect name. This plant is not related to H. rupifraga. The correct name is H. 'Hirao Monument'.
|In Hosta Mill Collection||Yes, the "European form" as available in trade.|