Hosta rupifraga

Hosta rupifraga (T. Nakai 1930/AHS 1993)

Subgenus Schmid Giboshi Zonneveld Giboshi
Section Schmid Picnolepis Zonneveld Picnolepis
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").
Leaf Petiole 25–7.5 cm (1–3"), rigid, blunt on back, not keeled, green.
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.
Inflorescense 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.
Blooming Time August
Fertility Fertile
Growing conditions  
Suitable for containers  
Special remarks

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.
Sports
  • H. 'Kihachijo' is the all yellow form.
Progeny
  • H. 'Amethyst Jewel' = H. rupifraga hybrid
  • H. ‘Barbarosa' (A. Malloy 2002) = 'Blue Splendor' x H. rupifraga
  • H. ‘Euphoria' (P. & J. Ruh 2002) = 'Sum and Substance' x H. rupifraga
  • H. ‘Forever Green' (J. Dishon 1994) = H. rupifraga x 'plantaginea'
  • H. 'Frosty Morn' = H. rupifraga hybrid
  • H. ‘Hirao Monument' (P. Ruh 2001) H. rupifraga hybrid
  • H. 'Hydon Twilight' = H. rupifraga hybrid
  • H. ‘Purple Essence' (P. & J. Ruh 2005) = 'Sweet Susan' x H. rupifraga
  • H. 'Rain Forest' = H. rupifraga hybrid
  • H. ‘Raspberry Sorbet' (M. Zilis 1999) = H. rupifraga x H. 'Shining Tot'
  • H. 'Rhapsody in Blue' = H. rupifraga hybrid
  • H. 'Roy's Pink' =  H. kikutii x H. rupifraga
  • H. 'Surfer Dude' = H. rupifraga x 'plantaginea'