Mallow-Leaf Ninebark Propagation

Mallow-Leaf Ninebark

• Known by a number of variations on its name, from mountain ninebark to few-flowered ninebark, this deciduous shrub grows in British
  Columbia, Alberta, Washington, Oregon, Idaho, Montana, Wyoming, Colorado, Utah and Nevada. The plant grows best on rocky hillsides, in dry canyon bottoms and in forests of yellow pine and Douglas fir. Its scientific name is Physocarpus malvaceus, and the plant is a member of the rose family. The ninebark grows from about 1-1/2 to 3 feet tall, with brown prickly branches and leaves that range from 3/4-inch to 2 inches in length. The leaves resemble those on small grape or currant vines and turn rosy-brown to bright red in the fall.

Flowering and Fruit

• Depending on the altitude, white flowers grow in dense, round clusters from late May through late July, according to the U.S. Forest Service. The small flowers have five petals and are about 1/2-inch in diameter. After flowering, reddish, fuzzy fruit appears. The rounded, egg-shaped fruit is about 1/3-inch in length and grows in pairs.

Seeds

• As the fruits mature, they split open to reveal the nineback's seeds. But the seeds do not immediately fall to the ground. Instead, they are dispersed by wind and browsing animals. In the wild,11 percent of the seeds that fall are viable and will grow new plants if they are covered by soil. The plants can also be propagated by picking the ripe fruit or shaking them from the shrub, according to the Lady Bird Johnson Wildflower Center. If the seeds are stored in a cool, dry place, they can be kept for five years or more.

Planting

• Mallow-leaf ninebark seeds can be sown in the fall or spring. For best results, the seeds should be chilled for 30 days before they are planted. The seeds should be sown just under the soil surface then mulched with a 1/4-inch of sawdust. Mallow-leaf ninebark can also reproduce from cuttings planted in the soil. Ninebark grows best in drier, rocky soils and needs little water. The shrub thrives in partial shade.