Advancing the Landscape Frontiers of Distylium
Distylium Blue Cascade®
Distylium Coppertone™
Distylium Emerald Heights®
Distylium Linebacker™
Distylium 'Vintage Jade'
By Michael A. Dirr, Ph.D.

In an earlier NMPro article (April 2009, 40-43), I discussed the Georgia breeding program with Distylium and the potential new introductions. Now with five years of field evaluation, propagation, and production, I am confident these Distylium hybrids are a powerful antidote to cherrylaurels, hollies, junipers, and other green meatballs. The initial three introductions are graceful, free-flowing, rich-foliaged, seemingly ironclad broadleaf evergreen that have passed muster at every challenge. Parentage is D. myricoides × D. racemosum. To date, the plants have proved bullet-proof to insects, diseases, heat, drought, cold, wind, and abiotic stresses. Easily rooted from firm-wooded cuttings and enthusiastically suited to container culture, they are a nursery producer’s delight.

The three are now named and in the patent process:

Emerald Heights® and Blue Cascade® are licensed to McCorkle Nursery (Dearing, GA) while 'Vintage Jade' is being introduced by Plant Introductions, Inc.  Liners and/or container-grown plants are available in 2011.

Characteristics: Original Selections, five-years in-ground, measured 03-07-2011, University of Georgia Horticulture Farm

Emerald Heights® ('PIIDIST-I' PPAF)―Compact, upright-rounded habit, with lustrous dark green, leathery leaves; small red flowers in leaf axils in February-March; parent plant 5.3' high and 8.4' wide; adaptable from zones 7 to 9; avoid late summer pruning so foliage fully hardens; liner will fill a three-gallon container in a single season; excellent alternative to Schipka cherrylaurel, as it resembles the latter in habit.

Blue Cascade® ('PIIDIST-II' PPAF)―Compact, spreading habit with the leaves held upright, resulting in a unique texture; leaves bronze-purple-red upon emergence turning dark matt blue-green and holding color year-round; red flowers are borne in leaf axils during February-March; parent plant 3' high and 7.8' wide; adaptable from zones 7 to 9; superior grouping or massing broadleaf evergreen for sun to partial shade; the foliage color and texture make this a standout introduction.

'Vintage Jade' (PP 23,128)―Branches layer, one-upon-the-other, resulting in a broadleaf evergreen with lustrous dark green leaves; red flowers open in February-March; parent plant is 2.2' high and 8' wide; adaptable from zones 6b to 9; perfect plant for covering large areas as the habit is groundcover-like.

These new introductions are primed and ready for integration into modern landscapes. Their adaptability to wet, yes wet, and dry soils is without parallel. The names, Distylium and Isu tree, are foreign to most gardeners and nursery growers. Given landscape opportunities, they will become "household" names. There are no messy fruits (small brown capsules the color of the older stems) or maintenance anomalies to frustrate gardeners and growers. Light tip pruning in June spurs new growth flushes and denser plants. A late winter tip pruning also works. Possibly the best advice is minimal attention.

A note on temperature tolerances and performance at the Horticulture Farm might open a few minds. The lowest temperature over the five-year period was 13.6°F. Michael Hayman, Louisville, tested Emerald Heights® and Blue Cascade® and plants survived 0°F in 2010 with foliar injury. 'Vintage Jade' was essentially unscathed. In 2010, 73 days of 90°F and above were recorded. The plants never flinched, only prospered.

Blue Cascade® habit
Blue Cascade® foliage