The mock orange shrub is one of the oldest flowering shrubs and has been domestically grown for nearly 400 years, as noted at PlantCare.com. It is a deciduous, flowering, rounded shrub that is easy to grow, reaching 8 to 10 feet high and 6 to 8 feet wide. The white blossoms are very fragrant and appear during late spring or early summer. Many people place the mock orange close to an entrance or walkway to highlight their fragrance. In landscape design, the mock orange is used as a specimen shrub or as a hedge/privacy screen. You must prune the mock orange to remove old growth, thin out new shoots and to maintain its space within your landscaping.
Cut off old growth after the shrub has finished flowering. Mature plants should have about one-third of the old growth removed. Removal of the old growth will encourage new growth, producing a healthier and more attractive shrub.
Prune branches where the growth has become extremely dense. Prune branches back to a healthy bud, cutting in front of the bud. The plant will develop new growth at that point. When you prune out old growth, it allows more sunlight in and improves air circulation.
Cut out any new shoots that are coming from the base of the plant, making your cut at the base of the shrub. Use your own judgment as to what shoots you prune out. Leave any new shoots that will improve the form/shape of the plant.
Thin the mock orange shrub by cutting branches back to where they attach to another main branch or to where they attach to the trunk once the shrub has finished flowering. It often works to do a combination of both pruning procedures--pruning new shoots down to ground level and cutting some branches back to where they attach to another branch or to the trunk.
View the mock orange from all angles to determine if you need to cut off any wayward branches. Also look for branches that are encroaching on other plantings. Prune as necessary, cutting just before a healthy bud.