Hydrangea hortensia Sieb. in Nov. Act. Nat. Cur. 24:11.688. 1829.
Shrub c. 1 m tall, almost glabrous. Bark cinnamon coloured, loose, peel¬ing off in papery strips. Leaves 3-17.5 cm long, 1.5-15 cm broad, elliptic or ovate, abruptly narrow at both ends, serrate, acute or sub-acuminate, glabrous; petiole 2-3 cm long. Inflorescence globose cymes, 8-22 cm broad. Flowers ebracteate, dimorphic, majority of the outer ones larger, sterile or functionally unisexual, a few central ones fertile, dull white, faded pink or bluish. Sterile flower pedicels 3-3.5 cm long, with sparsely appressed hairs; sepals 4-5, c. 2.8 cm long, 2.7 cm broad, rhomboid, light purple, prominently veined, retuse; petals rudimentary, usually 4, minute, c. 3 mm long, 2 mm broad, ovate, acute, spreading; stamens 8, filaments 1.5 mm long, slender; anthers 0.5 mm long; styles 2-3, 1 mm long, thick, divaricate; stigmas capitate. Fertile flowers penta¬merous; pedicels 3 mm long, sparsely covered with short simple hairs; sepals 5, small, triangular, 1.5 mm long, 1 mm broad, acute, fleshy, pink, persistent; petals 5, c. 5 mm long, 2.5 mm broad, elliptic-ovate, truncate at the base, acute, somewhat reflexed; stamens 10, filaments slender, 3 mm long; anthers 1 mm long; ovary inferior, styles 3-4, thick, c. 1.5 mm long; stigmas capitate.
Fl. Per. June-August.
Type: Described front China.
Distribution: A native of China and Japan, where it has been extensively cultivated for many centuries. Also cultivated in many parts of Asia, Europe and America.
“The Green House Hydrangea” is a small ornamental shrub, admired for its dull white, faded pink and beautiful blue flowers. Occasionally cultivated in the hill stations of W. Pakistan, where it can be propagated easily by cuttings.