Size and Appearance
The Eastern redbud, Cercis canadensis, is a large shrub or small hardwood, deciduous tree in the Fabiaceae (pea) family. Typically, redbuds are fast growers, reaching 15 to 30 feet tall and a spread of up to 35 feet. A mature redbud often has a gnarled or twisted, short trunk and wide, spreading branches. When young, they are usually vase shaped, with vertically outward branches that gradually spread out as the tree ages, eventually having a rounded or flat canopy. There are several cultivated varieties (cultivars) of the eastern redbud, which vary in mature size with many of them being dwarf or semi-dwarf types.
Redbud leaves are heart-shaped, and fairly large at 3 to 5 inches across. They are often blue-green in color. Some cultivated varieties have maroon-red or variegated foliage. It is a favorite tree species for gardeners and landscapers because of its spring time bloom, generally from late April through early May. As its name implies, the unopened buds are reddish-pink in color and open to a vibrant, purple pink color. Flower color may vary from tree to tree in nature, and especially in cultivation. Occasionally, the flowers are white. The redbud flowers are very typical for a legume, with a petal arrangement much like that of pea and bean blossoms.
Redbud, as mentioned is in the pea and bean family, and like most members of the family it has a relationship with nitrogen fixing bacteria in the soil. This relationship allows this species to thrive in soils where nitrogen is depleted as well as improve soil for other plants!
Native Range and Habitat
The Eastern redbud grows on wooded slopes, bluffs, upland woodlands, ridges, limestone outcrops and glades, woodland edges, and thickets. You can find it from Nova Scotia to Nebraska, south to Texas and northeastern Mexico, and east along the Gulf through much of Florida and northward along the entire Atlantic Coast to Massachusetts. This species is somewhat uncommon in nature in much of Pennsylvania. It can be found in the southern part of the state. Garden escapee populations and individuals can be found almost everywhere.
It is common in the Appalachian mountains, especially on south-facing slopes. It is most common in alkaline soils, with a pH above 7.5. Redbud is not typically found in northern Pennsylvania where most of the soil is acidic. The southern part of the state is limestone rich (high pH), including much of Lehigh County, where the redbud is occasionally seen in the wild!
There are three subspecies of Eastern redbud:
- Cercis canadensis var. canadensis (just known as Eastern redbud). This subspecies makes up the majority of the population, occurring in all but the southwestern part of the range. The Eastern redbud is endangered in New Jersey, and extirpated (no longer present) in both Delaware and Connecticut.
- Cercis canadensis var. texensis (called the Texas redbud). This subspecies occurs in parts of Texas and Oklahoma.
- Cercis canadensis var. mexicana (called the Mexican redbud). This subspecies occurs in parts of Southern Texas and northeastern Mexico!
The larvae of the Henry’s elfin butterfly, Callophrys henrici, feed on the foliage of the redbud as well as several moths including the redbud leaf-folder moth, Fasciata cercerisella. Several native bees including bumbleebees, mason bees, halictid bees, and others utilize the pollen and nectar of the redbud flowers.
Some birds, including the Northern cardinal and bobwhite quail (unfortunately, extirpated in Pennsylvania) feed on the seed of redbud trees, which look like tiny beans!
The Eastern redbud is a very popular tree for home gardeners and landscapers, which is always great to hear when its a native species! Its early bloom time, small size, fast growth, and relatively low number of serious pests and diseases makes it a great choice for many gardeners and landowners.
There are many cultivated varieties of redbuds including dwarf forms, weeping forms, and a diversity of foliage colors. We recommend avoiding dark-leaved (red or maroon) and variegated varieties because insects do not tend to benefit from them as much. Flower color also varies greatly in both nature and cultivation, from very light pink to magenta to near-red or violet, and sometimes white.
The Chinese redbud, Cercis chinensis, is a commonly grown ornamental shrub or small tree. It is very similar in appearance to our native Eastern redbud. The two species can be difficult to tell apart. Chinese redbud tends to have larger flowers, glossier leaves, longer seed pods, and grows to a shorter mature height (8-15 feet). Though found commonly in gardens, the Chinese redbud is not known to be invasive.
While their ranges do not overlap, there is another species of redbud native to North America: the Western redbud, Cercis occidentalis. Its extremely similar to both the native, Eastern redbud and the Chinese redbud in appearance but grows in the Southwestern United States.
Eastern redbud is easy to grow and low-maintenance! Its best grown on average to moist, well-drained, rich, neutral to moderately alkaline soils in full sun to partial shade. It tolerates a wide range of conditions including dry soils (once established), nutrient-depleted poor soils, slight acidity, rocky soils, and shade. Don’t try to grow it excessively moist soils, soil with poor drainage, and any soils 6.5pH or less.
Grow this species as a specimen, include within a mixed hedgerow or woodland edge, or grow as an understory shrub or tree. Protect from deer when young! You can prune redbuds as necessary but generally they do not require pruning. If you have limited space, consider a dwarf variety. Otherwise, we recommend planting the straight species when feasible to support genetic diversity and ecological function.