A deciduous shrub 5 or 6 ft high; young shoots furnished with appressed whitish hairs. Leaves pinnate, 4 to 5 in. long, composed of seven to eleven leaflets; leaf-stalk 11⁄4 to 11⁄2 in. long. Leaflets narrowly oval, tapered towards both ends, the apex terminated by a short mucro, 1⁄2 to 11⁄4 in. long, 1⁄6 to 2⁄3 in. wide, the terminal one the largest; there are pale appressed hairs on both surfaces, more abundant beneath; stalks 1⁄16 in. long. Racemes 3 to 41⁄2 in. long, slender, erect, produced continuously from the leaf-axils from June until October on very short peduncles. Flowers arranged closely on the raceme (ten or so to the inch) each 1⁄4 in. long, varying in colour from pale rose to deep pink. Calyx green, hairy, 1⁄8 in. long, with awl-shaped lobes of unequal length; flower-stalk 1⁄6 in. long. Pods 1 to 13⁄4 in. long, 1⁄8 in. wide, covered with close down.
Native of China. Plants at Kew obtained from Messrs Veitch in 1913 were introduced by Purdom from Kansu. Wilson found it previously in W. Hupeh, where it is abundant, and it was originally named from specimens collected by him in that province in June 1907. It is quite a pretty shrub, flowering over a long period when shrubs in bloom are not plentiful. It seems to be hardier than most of the indigoferas and its stems survive winters of at least moderate severity.
var. purdomii Rehd
Flowers slightly larger than in the type, lilac-pink. Described from plants in the Arnold Arboretum, raised from seeds collected by Purdom.I.
potaninii Craib – This species is closely allied to
I. amblyantha, the difference, according to Craib, being that the peduncle of the raceme is about as long as the petiole of the subtending leaf or slightly longer, but much shorter than the petiole in
I amblyantha. Perhaps a more reliable mark of distinction is that the leaves are shorter than in
I. amblyantha, 1{3/4} to 2 in. long, on shorter petioles {1/2} to {5/8} in. long, and the leaflets smaller, the lateral leaflets being {7/16} to {5/8} in. long, {1/8} to {1/4} in. wide. In describing this species Craib cited only the type specimen, which was collected by the Russian traveller Potanin in Kansu, but he later placed under it plants raised in the Arnold Arboretum from seeds collected by Purdom in Kansu under No. 539a. But judging from specimens in the Kew Herbarium taken from garden plants raised from Purdom’s seeds, it was not
I. potaninii but
I. amblyantha that Purdom introduced under No. 539a, and this was also Dr Rehder’s view. So it may be that most of the plants grown under the name
I. potaninii arc really Purdom’s introduction of
I. amblyantha, while those grown under the latter, correct, name represent the Wilson introduction from farther south.With regard to the true
I. potaninii, the only cultivated specimen in the Kew Herbarium is from a plant in the garden of the late Sir Frederick Stern, at Highdown in Sussex, which was raised from seeds collected by Farrer in Kansu under No. 260.I.
pseudotinctoria Matsum. – Leaves up to 2{1/4} in. long, with mostly seven or nine, occasionally eleven leaflets; leaf-petiole up to {5/8} in. long. Leaflets downy on both sides, the lateral ones {3/8} to {5/8} in. long, {3/16} to {5/16} in. wide. Flowers small, about {1/6} in. long, pale red to almost white, densely packed in racemes 2 to 4 in. long; peduncle of raceme very short. According to Craib it can be distinguished from
I. amblyantha by the shorter leaf-petiole, from
I. potaninii by the peduncle of the raceme being shorter than the leaf-petiole; the flowers are also much smaller than in
I. potaninii.Native of Japan, Formosa, and Central China; described by the Japanese botanist Matsumura in 1902; introduced to Kew by A. Henry in 1897 from Yunnan. Craib referred to this species plants found by Wilson in W. Hupeh, but these were true shrubs up to 8 ft high, while typical
I. pseudotinctoria is a subshrub less than 3 ft high. Whether the true species is now in cultivation it is impossible to say. The plant at Highdown in Sussex, which received an Award of Merit in 1965 under the name
I. pseudotinctoria, has not been examined, but it does not agree well with this species, judging from the photograph reproduced in
Journ. R.H.S., Vol. 90, fig. 180. The Highdown plant flowers early for an indigofera, from end-May.
