Photo: Mason Brock, Public domain · Wikimedia Commons

Softleaf Arrowwood

Viburnum molle

Also called soft-leaved arrowwood, Kentucky arrowwood.

A rare arrowwood of wooded limestone bluffs, with loose, peeling bark on its older stems and flat clusters of white flowers in May and June.

RareShowy flowersTolerates shade

Type: Shrub
Mature height: 6–12 ft
USDA zones: 5–7
Growth rate: Medium
Sun: Part, Shade
Soil moisture: Average
Grows wild in: Rich moist slopes, rocky ground, the forest understory and stream banks
Native range: 8 states, north and west to Iowa, south to Arkansas and east to Ohio
List all 8
Arkansas, Illinois, Indiana, Iowa, Kentucky, Missouri, Ohio and Tennessee
Also recorded in 6 other states, outside its native range. See what is native in your state

Hardiness zones Find your zone by ZIP code

Softleaf arrowwood is a rare viburnum of shaded bluffs and rocky slopes in the Midwest and the upper South, first described by André Michaux from Kentucky plants in 1803. It differs from our arrowwood viburnum in its long-stalked, nearly round leaves and in bark that peels in loose strips from stems more than two years old. Six states list it, Tennessee as endangered and Iowa, Illinois, Indiana, Kentucky and Ohio as threatened. NatureServe ranks it vulnerable. Plant it on a shaded slope or at the foot of a north-facing bank, where its peeling bark shows in winter.

Size, growth and what to expect

No source rates its growth, so our growth estimator treats it as a medium grower, like our arrowwood viburnum, about a foot and a half a year. It makes a bushy shrub 6 to 12 feet tall. Young shoots are bright green at first and soon turn gray.

Flat clusters of small white flowers, 2 to 4 inches across on long stalks, open in May and June. The fruit ripens from July into September, a flattened, oval, blue-black drupe up to half an inch long. The broad, nearly round leaves run 2 to 5 inches long, with 17 to 44 teeth along each side.

It grows wild in scattered stands from southwest Ohio, Indiana, Illinois and southeast Iowa south to Kentucky, Tennessee, southern Missouri and northwest Arkansas. Its home is shaded bluffs, talus and steep wooded slopes, usually over limestone. Records from Alabama, Maryland, Mississippi, New York, Oklahoma and Pennsylvania lie outside its native range.

How to grow Softleaf Arrowwood

Softleaf arrowwood grows wild in the filtered light under taller trees, so give it part shade. It wants a well-drained soil that stays moist, and in the wild it grows over limestone, on slopes above creeks but out of the floodplain. Plant it 6 feet from a wall and set plants 6 feet apart. At its size it can go within 15 feet of overhead wires.

Saplings ship bare-root or potted. Plant them dormant, from leaf fall until bud swell, in a hole wider than the roots and no deeper. Set the crown at the soil line, put the native soil back in, and keep the mulch ring clear of the stems. Its seed is untested, so sow it as northern viburnums are sown. Sow cleaned seed outdoors in fall or spring, half an inch deep, under wire against mice. Seedlings come up the second spring after you collect the seed.

Water weekly through the first summer if rain is short, and keep a mulch over the roots. Deer browse it in the wild, so cage young plants where deer are many. Keep bush honeysuckle, garlic mustard and other invasive plants from crowding it, since they threaten wild stands.

Each flower carries both male and female parts, and insects carry the pollen. Many Kentucky stands raise no young plants, perhaps because animals eat the seed or the stands are small.

Heights and zones are typical ranges for the species in cultivation; local conditions and seed source shift them.

Sources (13)