Catalpa ovata Slender Silhouette - Chinese catalpa

The Catalpa ovata Slender Silhouette is a variety that is easily recognisable by its narrow, almost columnar habit, which is quite different from other cultivars that tend to spread in width as they age. Its large heart-shaped leaves, in a beautiful green colour, give it a very exotic, almost tropical appearance, even though it is very hardy. This impression is reinforced by its summer flowering, in the form of long panicles of yellow flowers that somewhat resemble orchids. This tree with its unique graphic design and silhouette is well-suited for small gardens, especially in urban areas. It tolerates most soils and thrives in full sun, or even in light shade.

Catalpa belongs to the Bignoniaceae family, which includes more than 800 species of shrubs, trees, and climbing plants that often produce magnificent blooms. The flowering vines Campsis, Bignonia, Podranea, and other Tecoma are good examples, and some trees have among the most beautiful blooms, such as the Jacaranda with its prodigious and prolific blue trumpets. There are 8 to 10 species of Catalpa, with the most common being C. bignonioides.
Catalpa ovata is native to China and Japan, where it forms a tree with a straight trunk, reaching approximately 15 m in height. In China, its wood has been highly valued since ancient times and used for various purposes. Slender Silhouette is a horticultural variety that looks quite different from the botanical species. Much more compact, it usually reaches a height of 6 m with a spread of only 2 m, presenting a very narrow, almost columnar habit. The young plants form extremely upright branches, with stems as green as the leaves, which then darken. The leaves have a truly graphic aesthetic, with their overall heart shape, sometimes with indistinct lobes. They can actually measure up to 30 cm long and display a vibrant green colour. Emerging late in the season, they precede the flowering that appears from June and lasts into July. Tall panicles, measuring up to 25 cm long, rise above the mass of leaves, carrying approximately thirty flowers with the typical shape of the Bignoniaceae family. The tubular base widens into an asymmetrical trumpet with undulating edges, in a cream-yellow colour, marked with purple specks in the centre and two orange macules, which extend into dotted patterns of the same hue towards the centre. This magnificent flowering enhances the tropical appearance of this tree and emits a light fragrance reputed to repel flies and mosquitoes. The fruit that follows the flowers is equally impressive in size, resembling large beans that can reach 35 cm in length. Initially green, they turn black and persist on the tree throughout winter, further enhancing the uniqueness of its silhouette.

This Catalpa, with its unprecedented habit, can withstand extreme cold temperatures down to -28°C, making it a valuable plant for creating an exotic scene in the gardens of colder regions. It can be combined with other evocative plants, such as the Pawpaw (Asimina triloba), a slow-growing small tree that produces mango-shaped fruits with a mango-like flavour. A clump of Fargesia nitida Red Dragon, a medium-sized non-running bamboo with beautiful burgundy culms that contrast pleasantly with the green leaves, would also be a good addition to your flowerbed. The delicate leaves of the bamboo will create a visual contrast with the luxuriant leaves of the Catalpa. And in slightly milder climates, consider planting some clumps of Swamp Hibiscus (Hibiscus moscheutos) with their huge, brightly coloured flowers to complete the exotic feel of your plant scene.