The Mock Orange is a deciduous shrub growing in a rounded form 10 to 12 feet tall with arching branches. Some species in our western states are considered native to the U.S. Most species found in the east and central parts of the U.S. are native to Eurasia and are cultivated for their blossoms and fragrant scent. The nursery trade has developed a number of cultivars, with variation in leaf color, double flowers, and even scent-less blossoms. There are no species of Mock Orange native to Minnesota.
Bark is light brown, coarse and shreddy. Twigs have raised leaf scars.
Leaves are opposite and simple, somewhat oblong to ovate, usually with a few coarse teeth. They are light green and paler on the underside, with short stalks.
The inflorescence is an open cluster at the tips of twigs, composed of white flowers with 4 petals that are overlapping with rounded, somewhat wavy ragged tips. There are numerous stamens with yellow anthers; the ovary is 4-chambered with a style with a 3-lobed tip. Each flower is about 1 inch wide on a short stalk. The 4 lobes of the green calyx have triangular tips and are much shorter than the petals.
Seed: Fertile flowers produce a 4-parted cylindrical capsule containing numerous long narrow brown seeds. Old capsules, having dispersed the seeds, are persistent on the shrub.
Habitat: Mock Orange grows best in full sun with loamy well drained soils. Flower formation is poorer in partial shade. Most people consider the flowering period to be the only time of ornamental interest.
Names: The genus Philadelphus is from the Greek philadĕlphŏs which has two meanings: 1) Loving one's brother or sister, and 2) it was a Greek and Roman family name. For some time the word has been applied to the Mock Orange genus. The common name of Mock Orange is thought to come from England where the blossoms were used in country weddings to take the place of orange blossoms.
Above: The 1 inch wide stalked flowers occur in a loose cluster. Petals tend to have wavy somewhat ragged tips.
Below: Leaves are simple, on short stalks and usually with a few coarse teeth on the margins of the upper half.
Below: 1st photo - The flower clusters are open and loose in form. 2nd photo - The 4 green lobes of the calyx (sepals) have triangular tips and are much shorter than the petals.
Notes: The only time Mock Orange has appeared on a Garden census was the most recent in 2009.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"