One of the less well known of these is Leucothoe, which itself contains 44 species of deciduous and evergreen shrubs.
Dunedin Botanic Garden's Rhododendron Dell contains one of the evergreen species - Leucothoe fontanesiana - from the southeastern United States.
Cascading ground cover
In its native habitat, L. fontanesiana thrives in moist woodland, where the damp, shady conditions encourage it to heights of between one and two metres.
In the dell, although it is growing in damp shade, it does also have to compete with a large old Plagianthus tree, whose roots grow throughout the area.
As a result, the Leucothoe is barely a metre high.
At that height, however, it provides a welcome spread of stems and foliage that arch and cascade around the base of the Plagianthus and make a flowing link with the lower branches of surrounding rhododendrons.
In the spring, it carries racemes of white, bell-shaped flowers in the axils of the branches.
These can be partly obscured by the dense foliage but are beautiful nonetheless, with the white bells contrasting against the dark green leaves.
Trick of the light
Depending on the amount of sunlight to which it is exposed at this time of year, L. fontanesiana can also show some intriguing colour variations.
The shaded plants in the dell are still dark glossy green, but up in the North American border, in the geographic plant collection, where it is growing in afternoon sun, the leaves range from dark green at the base of the plant to deep purple-red on the exposed top.
Completing the picture, a scattering of yellow leaves makes the perfect highlight for the background of darker colours.
L. fontanesiana will not tolerate dry sites, however, so if it is to be grown in sun for autumn and winter colour variation, ample moisture and good drainage must also be available.
It is very hardy, tolerant of temperatures down to 20degC, but on exposed sites it can be burnt by cold winds. - Doug Thompson
Doug Thomson is the rhododendron collection curator at Dunedin Botanic Garden.
