ORNAMENTAL PLANTS OF HORTICULTURE VALUE
Selection of perennials
Gentiana L.
Gentian |
Gentianaceae |
About 300-800 species, depending on classification. Temperate
and arctic regions, montane elsewhere. About 65 species in the
FSU, including Gentianella, and about 40 species of
Gentiana s. str. There are representatives of different
sections: 7 species belong to the section Cruciata, 4 to
the section Frigida, 2 to the section Gentiana, 2
to the section Megalanthe. Some species have long been
in cultivation, e.g. G. lutea L. and G. punctata L.
(because of their medicinal properties), G. asclepiadea L.,
G. clusii Perr. et Song., G. cruciata L., G.
dahurica Fisch., G. decumbens L. f., G.
lagodechiana (Kusn.) Grossh. and G. septemfida Pall.
Some species have been investigated and recommended as prospective
garden plants, among them those described below.
G. dshimilensis C. Koch (sect. Chondrophylla)
Caucasus, Anatolia and Balkan Peninsula. In meadows in the alpine
zone.
Rhizome with numerous stems 3-8 cm. Rosette leaves lanceolate,
7-11 cm long; flowers solitary, bright violet, 2-4 cm long, sessile.
V - mid spring to early autumn. Fl - June-August depending on
locality and elevation. Fr - in July-October. Pr - by seed.
Requires a sunny position, humid air and limestone soil. Suffers
from excessive water in winter. Well suited for the rock garden.
Z 4. New.
A closely related species is G. grandiflora Laxm. from
southern Siberia and adjacent Central Asia. A low-growing plant
(2-4 cm) with numerous, large (2.0-2.5 cm), dark blue flowers.
G. kolakovskyi Doluch. (sect. Pneumonanthe)
Caucasus (southwestern regions). In meadows and on rocky slopes
in the subalpine zone.
Rhizome thick, vertical. Stems numerous, 15-40 cm, erect or
ascending, leafy. Leaves sessile, ovate or elongated, 3- veined,
30 (45) mm x 3-4 mm. Flowers solitary, terminal, campanulate, 50 mm
long, 10 mm wide, bright blue. V - mid-spring till mid-autumn. Fl -
July-August in the wild. Fr - August-September, not every year. P -
by seed. Requires a humus-rich soil and a partially shaded site.
Z 5 (4). New.
G. fischeri P. A. Smirn. (sect. Pneumonanthe)
Siberia (southern Altay and Dzungaria).
Stems numerous, erect, leafy, 50 cm. Lower leaves scale-like,
upper leaves oblong-ovate, 5 cm long. Flowers in dense terminal
clusters, campanulate, dark blue, interior green-spotted. V -
mid-spring to late autumn. Fl - late summer (August in the wild).
Can grow in sunny and partially shaded sites, requires a moist soil.
P - by seed. Z 5 (4). New.
The following are also of gardening interest:
G. owerinii (Kusn.) Grossh. (sect. Pneumonanthe).
Dagestan. Flowers in dense terminal, 4-8-flowered clusters, bright
blue-violet. V - mid spring to late autumn. Fl - July. Fr - October,
not every year.
G. paradoxa Albov (sect. Pneumonanthe).
Southwestern Caucasus. Flowers solitary, yellow-blue, almost brown.
V - mid spring to late autumn. Fl - August- September. Fr - October.
Both species can be propagated by seed. They require a humus-rich soil,
and partial shade. Z 5.
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