Cladrastis kentukea (synonym Cladrastis lutea), better known as yellowwood, is a relatively unknown tree that received its Dutch name because a yellow dye can be produced from its wood. Recently broken or sawn branches also show a characteristic yellow color. Yellowwood is a graceful medium-sized nectar tree for bees that deserves more attention. All year round, but especially in autumn when it turns a phenomenal golden yellow. Truly the tree of the month for October.
Summer bloomer
Cladrastis kentukea is a summer-blooming tree with a semi-open, rounded to broadly flattened crown with low branching. With its dense crown of compound leaves, it casts a pleasant dark shade in a sun-drenched garden. When pruned as a multi-stemmed tree, it is ideal as a foundation for a shaded border. Cladrastis kentukea is a beautiful, medium-sized tree up to eighteen meters tall with a short trunk. In cultivation, it often remains limited to twelve meters. The leaves are compound, inversely egg-shaped, emerge light green and turn dark green in summer. Yellowwood blooms spectacularly in June with fragrant white racemes of pea-like flowers. Not only people, but also pollinating insects such as wild bees, hoverflies, and bumblebees are very fond of them! Apart from a light pink flowering variant, there are no cultivars in circulation. In growth form or use, the pink variant does not differ from the species kentukea. In autumn, the brilliant golden-yellow foliage contrasts beautifully with the violet-gray bark and striking brown-green seed pods. Despite its preference for a sunny and warm spot, Cladrastis kentukea is quite hardy.
Impressive appearance
Yellowwood makes an impressive statement in parks, public spaces, and large gardens. The species has a strong root system and is undemanding when it comes to soil conditions. Cladrastis kentukea originates from valleys with warm microclimates, where it grows on well-drained, moist, and often calcareous soils. Its natural habitat is forests, especially along open, higher parts of riverbeds with tall perennials at their base. In cultivation, the tree also thrives well on acidic soils.
Nitrogen fixing
Cladrastis kentukea belongs to the Fabaceae (pea family). An important feature of legumes is their ability to fix nitrogen. By capturing nitrogen from the air, they enrich the soil and improve fertility. Generally, they are also drought tolerant — and so is yellowwood. Apart from a sheltered location with light shade to protect against sunscald, yellowwood requires little. It needs minimal maintenance, and if pruning is necessary, the summer months are most suitable because of winter bleeding.
Choosing Cladrastis means choosing a tree that stands out for its graceful growth habit. Closely related genera include Maackia and Styphnolobium.
