Variations 
var. albiflorus
This slow-growing deciduous shrub forms a compact habit from ground level up to 4 m tall (12 ft) by 2 m (6 ft) wide with a dull green leaves that turn vivid orange red during autumn before falling. From mid-spring to early summer it produces white bell-shaped flowers in pendant clusters. 

It prefers a full sun to semi-shaded protected position and grows in well-drained fertile, reliably moist soils that are tending acidic. It grows in USTA zones 5-8.

var. palibinii
This deciduous shrub is similar to the species forming a rounded compact habit from ground level up to 4 m tall (12 ft) by 2 m (6 ft) wide. It has dull green leaves that turn vivid orange red during autumn before falling and from mid-spring to early summer it produces strongly reddish bell-shaped flowers in a pendant cluster. 
It prefers a full sun to semi-shaded protected position and grows in well-drained fertile, reliably moist soils that are tending acidic. It grows in USDA zones 6-9.

Cultivars
'Red Bells'
This deciduous shrub forms dense branching from ground level up to 4 m tall (12 ft) by 2 m (6 ft) wide with a dark green whorled leaves that turn orange-red during autumn before falling. From mid-spring it produces creamy white bell-shaped flowers that are suffused in red and appear in a pendant cluster. 

It prefers a full sun to semi-shaded protected position and grows in well-drained fertile, reliably moist soils that are tending acidic. It grows in USDA zones 5-8.

'Showy Lantern'
This deciduous shrub forms a dense branching from ground level up to 3 m (12 ft) tall by 2 m (6 ft) wide with a dark green leaves that turn scarlet during autumn before falling. From late spring to early summer it produces deep pink bell-shaped flowers with a red veins in large clusters. 

It prefers a semi-shaded to full sun protected position and grows in most well-drained fertile moist soils that are tending acidic. It grows in USDA zones 5-7.

'Variegata'
This rare shrub is similar to the species forming a rounded compact habit from ground level up to 4 m tall (12 ft) by 2 m (6 ft) wide. It has dull green leaves with a whitish margins and red petioles and turn orange red during autumn before falling. 

It prefers a full sun to semi-shaded protected position and grows in well-drained fertile, reliably moist soils that are tending acidic. It grows in USDA zones 7-9. This plant is not commonly cultivated and may be difficult to obtain requiring a specialist nursery.