Description from Flora of China
Shrubs ca. 4 m tall. Branchlets of previous year dark purple, glabrous, those of current year purple, densely gray-yellow villous. Petiole 5-10 mm; leaf blade ovate or ovate-lanceolate, rarely narrowly lanceolate, 2-6 × 1-3 cm, abaxially densely villous, adaxially sparsely so, veins 3-5, slightly basifugal, base rounded, margin entire or sparsely serrulate, apex acuminate or abruptly so. Racemes 5-8 cm, (5-)7-13-flowered, lowest ones usually 3-flowered cymes; rachis and pedicels densely gray-yellow strigose; pedicels 1-12 mm, distal ones usually shorter. Calyx tube densely gray-yellow strigose; lobes ovate or ovate-lanceolate, 4-5 × 3-3.5 mm, apex acuminate, acumen ca. 1 mm. Corolla discoid; petals white, obovate or suborbicular, 4-5 × 3.5 mm. Stamens 27-30, longest ones ca. 7 mm. Style entire or slightly divided, robust, slightly shorter than longest stamens, glabrous; stigmas clavate, 1.5-2 mm, subequaling anthers. Capsule gray-brown, turbinate, ca. 7 × 6 mm. Seeds ca. 2.5 mm, shortly tailed. Fl. Jun.
Philadelphus kunmingensis and its var. parvifolius were previously published by Hwang (Acta Bot. Austro Sin. 7: 5-7. 1991), but were invalid because no type was cited (St. Louis Code, Art. 37.1).
* Thickets; 2000-2100 m. Yunnan.