Lewis's Mock Orange

Growing Lewis's Mock Orange

Idaho's state flower, and one of the few Western natives grown purely for scent. Prune right after flowering; it blooms on old wood, so a spring cut removes the whole show.

Where it belongs

Mock orange grows on rocky slopes, canyon walls, streambanks and open woodland from British Columbia south through the interior Northwest and into the northern Rockies. It is Idaho's state flower.

Meriwether Lewis collected it in 1806, which is where the species name comes from. It is one of very few Western natives grown primarily for scent rather than for looks, structure or wildlife value, though it happens to offer those too.

Growing it

It is a loose, upright shrub, five to ten feet tall, with arching stems and plain green leaves. For two or three weeks in late spring and early summer it carries four-petaled white flowers in clusters along the previous year's growth, and the scent carries across a yard on a warm evening.

Full sun gives the heaviest bloom. Part shade is fine and produces a looser, taller plant. It takes ordinary garden soil, rocky ground, or a dry slope, and once established it does not need summer water in most of its range.

The one thing that will cost you the flowers is pruning at the wrong time. It blooms on wood grown the previous year, so a tidy-up in early spring removes the entire display. Prune immediately after flowering, and only to take out the oldest stems at the base.

What it feeds

The open flowers are easy for a wide range of insects to reach, and bumblebees, solitary bees, syrphid flies and butterflies all work them. It is a nectar plant rather than a host plant for most of the season.

Birds use the dense arching structure for nesting more than they use it for food, which is a fair trade in a shrub this size.

Living with it

Site it by a door, a path, a window that opens, or wherever people sit in June. The scent is the reason to grow it and it is wasted at the back of a property.

Out of bloom it is an unremarkable green shrub, so it works best with something in front of it rather than alone in the middle of a lawn.

It’s fragrant, drought-tolerant, deer-resistant, showy, and easy to grow.

Where it grows

Lewis's Mock Orange is native to the Pacific Northwest. In the wild you’ll find it across Arizona · California · Colorado · Idaho · Montana · New Mexico · Oregon · Utah · Washington · Wyoming. Always confirm it suits your specific county with your state native plant society before planting.

Regional Garden has written state guides covering Lewis's Mock Orange in 10 of them so far.

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