Clematis, Tangutica Overview Category: Vines Common Name: Clematis, Tangutica Botanical Name: Clematis tangutica Sun Exposure: Full sun Height: 15-20 ft. Spread: Varies See notes | Back to vines Notes Golden yellow, bell-shaped flowers, 1". Attractive seed heads, suitable for cutting. Blooms July- October. Prune heavily early Spring to buds almost at ground level.