The Northern Catalpa is surely one of the most spectacular flowering trees of the temperate zones. It has huge, light green, heart-shaped leaves and large, wonderful clusters of white, fragrant, frilly flowers in the springtime. It looks like it is a tree from from a tropical jungle, rather than the temperate regions and it is, in fact, related to a number of tropical flowering trees. It is one of the few hardy members of the mostly tropical Bignoniaceae family, which includes has many exotic flowering trees and vines. Catalpa speciosa is a medium to large, deciduous tree that typically grows to 40-70’ (less frequently to 100’) tall with an irregular, open-rounded to narrow-oval crown. It is native to a relatively small area extending from western Tennessee, northeastern Arkansas and the lowlands of southeastern Missouri north to southern Illinois and southern Indiana.
Broad ovate to ovate-oblong leaves (to 12” long) are pointed at the tips and rounded to cordate at the bases. Leaves are light green to yellow green above and densely pubescent below. Foliage turns light yellow in the autumn. Flowers can be a real showstopper, however. Bell-shaped, orchid-like white flowers (to 2” long) with purple and yellow inner spotting appear in panicles in late spring (late May to early June in St. Louis). Flowers give way to long slender green seedpods (12-22” long). The seedpods mature in fall to dark brown and then split open lengthwise to release the seeds within. Seedpods give rise to the common name of cigar tree, although they actually are longer and thinner than most cigars. Abundant pods are produced every 2 to 3 years. Bark of mature trees is fissured, prominently ridged and pale gray-brown.
A mature, symmetrically rounded catalpa tree can be a tree of great beauty, particularly in spring when the foliage is young and the flowers are in bloom. It has been widely planted in urban areas as a street tree and lawn tree, and can also be effectively used in the landscape for difficult areas such as moist low spots or dry areas with poor soils. It is easily grown in average, medium to wet, well-drained soils in full sun to part shade. Tolerant of a wide range of soil conditions including both wet and dry soils. Tolerant of seasonal flooding. Prefers moist fertile loams. Hardy in zones 4-8.