What: One of the most delicate and delightful vines, Clematis “Betty Corning” produces a long procession of nodding flowers from mid-summer until early autumn. The lavender-blue petals dangle from long flower stems and give the appearance of ballerina skirts floating in the air. Although this clematis has good garden vigor, it will not overrun its neighbors. Its open-growth habit makes for a lovely scene running through large shrubs or small trees. As with all Clematis viticella selections and most of their hybrids, this vine has good resistance to clematis wilt.
Where: This clematis will grow best in full sun to light or open shade. Provide a location with rich and well-drained soil, where it can be regularly watered during dry weather.
Size: “Betty Corning” will grow to 20 feet long with a spread of 3 feet when mature.
Care: Plant vines that are well rooted and at least two years old. In our climate, planting too deeply can smother the roots. Set young plants at the same depth they were in their nursery pots. Clematis are heavy feeders and appreciate fertilizing in spring. This clematis blooms on new growth, so it is best to prune in winter. Remove congested or tangled growth and thin to the strongest stems. Well-established plants can be cut back to 12 inches tall in winter to remove large tangles, allowing robust new stems to fill out the plant.
— Richie Steffen, Great Plant Picks