Batten Blooms
PL. —Cotinus coggygriaBotanical illustration — drop image
Cotinus coggygria

Smoketree 'Royal Purple'

SpringSummerFall
5a–8bHardiness zone
Peak bloom windowZone 6b · frost-offset weeks
Winter
Not in bloom
Spring
Peak bloom
Summer
Peak bloom
Fall
Not in bloom
Peak bloom
In bloom
Background

'Royal Purple' is a widely planted smoketree cultivar selected for its deep maroon-purple foliage, among the darkest of any smoke bush selection. New leaves emerge nearly black-purple in spring, hold rich purple through summer in full sun, and turn scarlet-orange in fall. Its pinkish-purple smoke plumes echo the foliage color, giving the whole plant a more unified, moody look than the green-leaved species.

Full sun is necessary to hold the dark color — in shade, leaves fade toward green. Like the species, it performs best in lean, well-drained soil and resents rich, consistently moist ground, which produces lax growth. Cut hard to a low framework in late winter for the largest, darkest leaves on a compact plant (sacrificing that year's smoke plumes), or prune lightly after flowering to keep both bloom and a looser, more natural shrub form.

Good companions
Purple ConeflowerStonecropSalviaAmsonia
Care guide
SunFull sun
WaterLow to moderate; drought tolerant once established
SoilLean, well-drained; tolerates poor, dry, rocky, alkaline soil
Spacing10–15 ft
Height10–15 ft
Zone5a – 8b
Frost hardy
Seasonal tasks
spring
watchWatch for sudden one-sided branch wilting, a sign of verticillium wilt; prune out and destroy affected wood well below any staining in the sapwood.
cutCut all stems back to a low framework before growth begins for the largest, darkest leaves on a compact plant, sacrificing that year's smoke plumes; prune lightly after flowering instead to keep both bloom and a looser shrub form.
sowPlant in spring in full sun, which is necessary to hold the deep purple foliage color — shade causes leaves to fade toward green.
summer
watchPinkish-purple smoke plumes build through early-to-mid summer, echoing the foliage color.
cutCut smoke-stage stems for arrangements once plumes are fully expanded; they dry well and hold color for months.
fall
watchDeep purple leaves turn scarlet-orange as nights cool in fall.
Common problems

Verticillium Wilt

Symptoms

Lower leaves yellow and wilt, often on one side of the plant, with brown streaking in the stem and crown tissue when cut open. Plants are stunted and decline over the season.

Treatment

Remove and destroy affected plants. Avoid planting in soil that has grown infected tomatoes, peppers, or other susceptible crops. Rotate beds and improve drainage; there is no cure once a plant is infected.