Sherry Sue Summersweet

'Sherry Sue' is a Clethra alnifolia selection whose new wood comes in pinkish red, which gives the shrub something to look at months before the flowers arrive. It settles at 5–6 ft in both directions — full size for the species rather than a dwarf — and carries the fragrant white bottlebrush spikes the genus is grown for, opening in mid to late summer, later than almost any other hardy flowering shrub. Autumn foliage turns clear golden yellow, and the small seed capsules hold on through winter as minor bird forage.

Wild Clethra alnifolia runs down the coastal plain from Nova Scotia to Florida and west into eastern Texas, in wetlands, bog margins, and stream edges, and what it wants in a garden follows from where it grows: acid soil around pH 4.5 to 6.0, steady moisture, and no objection to ground that stays wet. Dry soil is the one condition it will not forgive. An organic mulch — pine bark or shredded leaf — holds water and keeps the root zone sour. Sun buys the heaviest flowering; the plant stays structurally sound in part or even deep shade, with fewer spikes to show for it. It breaks dormancy late, so wait for new growth before cutting anything that reads as dead in spring. Underground stems build a dense clump over the years, which is an asset holding a damp bank or filling a low corner; where it is not wanted, suckers come off cleanly at ground level.

Flowering after midsummer forage has thinned is what makes it ecologically useful — bumblebees, honeybees, and a range of native solitary bees work the spikes hard. In New York the species keeps to acid ground in the southern half of the state, along pond edges, sphagnum wetlands, and bogs. It is easy to find around the lakes at Minnewaska, usually with swamp azalea (Rhododendron viscosum) close by, and it drops out almost entirely in the Catskills. Older books and a good many nurseries still sell it as sweet pepperbush.