Eastern Ninebark Physocarpus opulifolius and Western Ninebark Physocarpus capitata are the most popular types of Ninebark in nurseries today. Many cultivated varieties of Eastern Ninebark have emerged in the past ten years offering a selection of leaf-color and mature sizes that are very garden worthy.
Flowers on Eastern Ninebark are white, opening from red buds and eventually forming a fruit that is edible for birds. All lose their leaves in winter to reveal striped bark that peels off in sheets, and all adapt to differing site conditions, making them an easy addition to the landscape. Several of these varieties are discussed in this article.
The Western Ninebark is native to the Pacific Northwest and is one of our Native Plant Picks.
'Center Glow' – Leaves are purple with a gold center when they first emerge in spring and turn red and purple as they age, but the coloration is less dramatic in mild weather. Fall color is scarlet red. The shape is upright with arching branches. Grows 8-10' x 8-10' – Sun, part shade – Hardy Z2, -50f.
'Coppertina' – New leaves are orange and turn red as they mature. Growth is upright & fountain shaped, slightly more narrow than 'Center Glow'. Grows 8-10' tall, 5-6' wide – Sun, part shade – Hardy Z3, -40f.
'Dart's Gold' – Bright gold new leaves, sometimes tinged red turn chartreuse toward the center of the plant where light doesn't make its way in. 'Dart's Gold' shows its color best when it has morning sun and afternoon shade, or dappled light. It grows in an upright fountain shape. Grows 5' x 5' – Part shade – Hardy Z2, -50f.
'Diablo' – Dusky dark purple leaves turn red in autumn before falling. Shape is upright and arching. Grows 8-10' x 8-10' – Sun, part shade – Hardy Z2, -50f.
'Little Devil' – Aptly named, 'Little Devil' is much like 'Diablo', just smaller in every way; smaller (cuter) leaves, smaller (cuter) stature, smaller (cuter) flower clusters. Leaf color is different in that it's brighter red and glossy where 'Diablo' is matte. Stems glow red and leaves turn green on the interior of the plant.
'Little Devil' is brand new and we were fortunate to find the few we were able to stock this summer, which are now sold out. We eagerly anticipate stocking more in spring 2011. Grows 3-4' x 3-4' – Sun, part shade – Hardy Z2, -50f.
'Summer Wine' – Red leaves are bright when they first emerge and darken just a little. Leaves are a tad smaller than 'Diablo' too. The shape is upright and arching. Grows 5-6' x 5-6' – Sun, part shade – Hardy Z2, -50f
Family: Rosaceae, the Rose family
Genus: Physocarpus (f-eye-zoe-CAR-puss) In Greek, physa means 'bladder' and karpon means fruit, referring to bladder-like fruit.
Common Name: Ninebark
Origin: Most species are native to North America. Just one, Physocarpus amurensis is native to Korea and Manchuria.
Characteristics: Clusters of reddish pink flower buds open to white or pale pink flowers in spring. Leaves are alternate, simple, 3-5 lobed, and can be green, purple, red or yellow.
Leaves turn yellow, orange or red before falling in autumn to reveal bark peeling in long sinuous pieces. Fall berries are small, seedy and hairy – great for birds and not bad to look at. Grows upright in a broad fan or fountain shape.
Size: Most are large shrubs, growing 6-10' tall and wide. A few varieties are smaller-growing, to 3-5'.
Culture: Physocarpus is very adaptable. Wet soil, dry soil, nutrient rich soil, poor soil, full sun, part shade, Physocarpus is not picky. Some of the purple-leaf types can turn a bit green in summer heat, and gold-leaf types appreciate some afternoon shade or additional water to keep from burning. All Physocarpus are cold tolerant to -30f or colder.
Disease: Being a member of the rose family has an obvious down side; disease problems.
Physocarpus is not prone to all rose diseases, but is subject to powdery mildew that coats the affected leaves in white fuzz. Use rose fungicides to fight it off, or just remove and discard (don't compost) affected leaves to keep spores from spreading. When leaves fall in autumn, remove persistent foliage from branches.