Philadelphus lewisii is also known as Lewis’ Mock-orange, Gordon’s Mock orange, Indian Arrowwood, California Mock Orange, Wild Mockoranage, and Syringa. Though Syringa is used for Lilacs. Philadelphus lewisii is part of the Hydrangeaceae family of plants.
It is native to Western North America. From California north to British Columbia and east to Montana. The name refers to the person who discovered it first Meriwether Lewis during the Lewis Clark Expedition or Corps of Discovery Expedition from 1803-06.
Philadelphus lewisii can grow to 3m or 10ft. The stems are reddish when young and later turn gray. The foliage is opposite medium green, oval. It is smooth or serrated with a rough texture. Philadelphus lewisii flowers in clusters of white four-petal clusters at end of stems. Each flower has prominent yellow stamens. It could flower profusely making a strong impact on your landscape.
The flowers are fragrant with a similar scent to oranges. therefore the common name Mock Orange. It flowers for several weeks on the previous year’s wood or growth. It usually flowers in late spring or early summer. It produces a small capsule fruit with many brown seeds.
Grow Philadelphus lewisii in the sun or partial shade. It tolerates a variety of soils. It is drought-tolerant, but don’t starve it of water as it might affect flowering. It is generally disease and pest-free. Watch out for leaf spot, canker, powdery mildew, and rust. Prune after flowering. It can tolerate hard pruning if it is necessary.
Philadelphus lewisii wood was used by Native Americans for hunting and fishing tools and pipes. The leaves and the bark contain saponin, which works as a mild soap. The flowers with their fragrance were used for tea or perfume.