Star Gardener: Plants Have Ears

Last summer I was obsessing over the purple-leaved redbud Cercis canadensis Forest Pansy
Forest Pansy in mid-May Abby Jane Brody

I swear plants can understand us.      
Last summer I was obsessing over the purple-leaved redbud Cercis canadensis Forest Pansy. It had been planted in the early 1990s behind a large oak, and only glimpses of the foliage could be seen from the lawn and the house. It was perfect and charming. Two years ago the oak came down, and there was Forest Pansy in all its gorgeous glory. It was very large and upright, not umbrella-shaped like most. The color of its foliage was so strong everything nearby was overwhelmed and diminished.

What to do? My complaint was it had grown too large. I spoke of having it pruned drastically to bring it into balance with its neighbors. If that didn’t work, it would be removed.

The tree clearly heard my threats. Winter came and with the long stretch of bad weather nothing was done.
In mid-May it was a spectacle, with more intense pink flowers than ever.  It was echoed by an azalea underneath, with flowers in a similar color.

I should have known something was up. The horticulture books say that just before a plant dies it produces a superabundance of flowers and seed.

Two of the large lower branches leafed out normally while the rest of the tree was bare. Forest Pansy is a tree with a reputation. It has a habit of losing a couple of lower branches every year; eventually the losses add up and the tree declines badly or dies.

As the season has progressed the entire central portion has few leaves, and some of the dead branches have been removed, leaving a less than aesthetic shape. Juan, my gardener, ever the optimist, says it has ninos and I should just be patient. I’m convinced he is wrong, and from apparent robust health last year it is exacting revenge for my callous thoughts and is dying, slowly but surely, before my eyes.

With a heavy load of gardening chores, we shall do nothing now, and perhaps patience will win out. In the meantime I am ruminating about possible replacements.

Aside from purple-leaved European beeches that are too large to integrate into the edge of a woodland garden, perhaps the most popular possibility is the cherry plum Thundercloud (Prunus cerasifera Thundercloud). No, no, and no again, I say. In fact, I think nurseries that sell it to well-intentioned homeowners are perpetrating a (minor) crime. Purple plums are susceptible to almost every pest and problem infection there is, and as a result, they are short-lived.

High up on the list is a new Japanese snowbell found in the Netherlands and introduced in very small sizes by specialist nurseries in the United States last year. It is Styrax japonicus Evening Light. It flowers prolifically even while young, and is fast-growing. It has grown nearly a foot so far this season.

The new leaves are glossy deep purple. Plant it where it receives as much sun as possible, as the leaves will turn green if it is in too much shade. It won’t take long for good-sized trees to vie for space in our local garden centers. In the meantime, Broken Arrow in Hamden, Conn., carries it.

Another possibility is to stick with redbuds and try a new purple-leaved hybrid, C. canadensis Merlot. Most redbuds are somewhat finicky and are not supposed to be salt-tolerant, a handicap in our area. The early flowering in bright pink makes it alluring as an ornamental tree.

Merlot is reportedly hardier and more heat-resistant than Forest Pansy, thanks to its original mother, Texas White. Seed was collected from Texas White, growing next to two plants of Forest Pansy on the campus of North Carolina State University in Raleigh, after the 1998 growing season. Merlot was selected from second-generation seed because of its glossy purple foliage and semi-upright growth habit. From original hybridization to its 2009 release by the university took 11 years. It is reported to have smaller, thicker, and glossier leaves than Forest Pansy and has a tighter, denser habit, which certainly would do away with my complaint that Forest Pansy is too large for its site.

The solution is probably to get both the styrax and the redbud, grow them on, and put off a decision as long as possible while enjoying each.

As for Forest Pansy . . . ?