Clematis heracleifolia, the tube clematis, is a species of flowering plant in the buttercup family Ranunculaceae, native to central and northern China. Unlike most other members of the genus tube clematis, it has a scrambling rather than a climbing habit. Growing to 1 m tall by up to 50 cm broad, it is a deciduous sub-shrub with broad downy leaves in groups of three, and delicate clusters of elongated tubular blue flowers in late spring and summer. Mature blooms recurve into a trumpet shape. Repeat flowering sometimes occurs in autumn. The Latin specific epithet heracleifolia means "with leaves resembling hogweed" (Heracleum). The cultivar 'Cassandra', with fragrant flowers, has won the Royal Horticultural Society's Award of Garden Merit.