Cercis canadensis 'Green Machine' - Green Machine Weeping Redbud

Few would argue the Eastern redbud (Cercis canadensis) is one of the finest ornamentals among small flowering trees. Because of this, horticulturists have bred and introduced numerous cultivars (short for “cultivated varieties”) over the past few decades. This cultivar is called ‘Green Machine.'

The flowering habit of the Eastern redbud is unique among trees with pink-red buds forming along branches throughout the entire crown (not just branch tips) in March and early April. These buds open to reveal pink-purple flowers in mid-April here in western Pennsylvania and last around three weeks. Redbuds are easy to identify when flowering as they appear to have a pink silhouette around most of the tree, even along thick, older branches. This trait is shared by both upright and weeping cultivars. As flowers fade, heart shaped leaves begin to form. Fall color is usually a modest but respectable yellow.

‘Green Machine’ is a weeping cultivar with a particularly vigorous habit, developed by Garden Debut. The foliage is a standard green which lends itself to greater horticultural versatility than burgundy and chartreuse foliaged redbuds. A mature specimen is 6-10 feet high and wide, with the spread being somewhat greater than the height. Site in a location where ‘Green Machine’ can retain its form by letting the branches weep to the ground for maximum effect. Resist urges to prune or trim aside from occasional stray or dead branches.

Redbuds have been, somewhat unfairly, viewed as temperamental (some have even dubbed them as "deadbuds"). The key to success, however, is understanding how and where the species grows naturally and how to site and/or mimic these conditions in the landscape. If a few conditions are met, Redbuds are fairly adaptable and easy to grow.

Eastern redbud is native throughout most of the mid-Atlantic, Southeast, and central parts of the United States with Pennsylvania and Michigan occupying the northern limits of its range. It's generally found growing in the understory and along the edges of forests and woodlands, often on upland slopes in neutral to slightly alkaline soils (e.g., limestone). As an understory tree, redbuds prefer part sun when planted in our gardens and landscapes. They will, however, grow well in full sun if planted in the vicinity of other trees and vegetation. This helps moderate intense wind exposure and extreme temperatures. Avoid planting redbuds as stand alone specimens in empty, exposed areas and site them away from surfaces that dramatically heat up in the summer months such as asphalt, cement, brick, and extensive river rock.

Eastern redbud is adaptable to a variety of soils as long as drainage is good. They grow well in neutral to slightly alkaline soils - where they frequent in the wild - but they'll also will grow in average acid soils that exist in most home gardens. They also grow well in clay soils as long as they don't accumulate too much water after rainstorms. As a member of the pea family, they colonize bacterium in and along their roots to foster and "fix" nitrogen. This trait enables redbuds to thrive in leaner soils. As such, you don't need to concern yourself with fertilizing. Once established, redbuds will tolerate dry spells (although a little supplemental watering during long droughts is a good idea).

As a regular component of eastern forests and woodlands, Eastern redbud contributes a host of ecological services. The flowers are an important source of nectar and pollen for queen bumblebees in spring when they emerge from hibernation and begin to build nests. In summer, you may notice sporadic, circular shaped cut outs from the foliage. These are the handiwork of indigenous leaf cutter bees. These bees are solitary, nonaggressive bees that use these leaf cut outs to build tubular nurseries for their offspring. ‘Green Machine’ provides these same ecological services albeit on a smaller scale due to its reduced size as a weeping specimen.

Fun fact: many parts of redbuds are edible. Many opine that the flowers have a subtle floral sweetness with a slightly tart aftertaste. Developing seedpods, when they are purplish-green, resemble snow peas and can be similarly used in salads and stir fry.

If deer are a problem for you, we recommend you provide your tree with protection, such as a metal cage, until the tree is large enough to not be severely damaged.

Written by Plumline staff and not AI.