A ninebark shrub is one of the most versatile and easy-to-grow shrubs available to Prairie gardeners. There are several varieties that make using it even more useful when planning a landscape, as one with the appropriate leaf colour and one that grows the desired height can be selected from a long list.
One of the original varieties is “Diablo,” which is a tall shrub reaching a height of well over three metres. Its dark-burgundy foliage is its main attraction and the leaves are lobed and veined and produced on upright branches, so it doesn’t get as wide as some other shrubs. It is multi-stemmed and multi-branched, and although it prefers full sun (any shrub with coloured foliage will be more vivid when exposed to lots of sun), all ninebarks will perform in part shade. There will be slightly less bloom in such an exposure. Like all shrubs, when newly planted, a ninebark should be kept well watered until it gets established. After that, it is incredibly drought tolerant and will endure long periods without rain.
“Diablo” is the largest of the ninebarks but there are smaller varieties. “Little Devil” has similar coloured foliage to “Diablo,” but only grows about 1-1/2 metres tall. Its flowers tend to have a purple tint whereas those of “Diablo” are white. Ninebark flowers are produced in clusters or umbels and the individual flowers are cup shaped. They appear in June and July and then are replaced by red seed heads which add colour during late summer and fall. The flowers attract bees, butterflies and even birds like these shrubs — but so do deer. Although aphids and mildew can appear, they are not persistent problems.
Besides the burgundy-leafed ninebarks, there are varieties that have gold foliage. “Amber Jubilee” has vibrant multicolours of orange, yellow and gold, while “Dart’s Gold” is a pure gold colour. Both produce white flower umbels. “Amber Jubilee” is the shorter of the two, growing to a height of two metres, whereas “Dart’s Gold” will reach almost three metres. Both have an upright growth habit. Positioning a burgundy-leafed ninebark near one with gold foliage creates a nice contrast.
Because ninebarks are fast growing they require consistent pruning. The best time to prune is in spring before they leaf out, but pruning will also remove some of the flower buds so flowering will be reduced. Ninebarks do not resent pruning and can be clipped throughout the year. If a shrub gets too woody and overgrown it might require rejuvenation pruning where it is cut back to just about ground level; new growth will soon emerge and produce a healthy shrub. Renewal pruning might be done on an annual basis; this involves removing a few of the most mature stems each year right back to ground level. In this way the shrub never gets overly woody or overgrown and always consists of relatively new stems (the standard practice is to remove from one-third to one-quarter of the stems each year).
Because ninebarks are versatile in terms of sun exposure, they can be used in many locations. They are also not fussy about soil type and will grow well in a dry spot or in one that is more constantly moist. All can be used as specimen shrubs, and pruning will give them the desired form and size. The smaller varieties are good to use in xeriscape landscapes, and the taller ninebarks make good loose privacy hedges. They also provide excellent contrast in a shrub border with their red bark colour.
A ninebark shrub can be used to anchor a large flower border, or a formal clipped hedge could also be created. These beautiful shrubs are versatile and perform well with little care — a definite asset to any landscape.