Garden center customers frequently come to me with questions like, “should I prune mock orange that didn’t flower this year.” My answer is: yes. For the overall general health of the shrub, mock orange pruning should be done once a year, not just when it doesn’t bloom or has gotten overgrown. Even dwarf varieties need a good pruning each year. Continue reading to learn how to trim mock orange shrubs.
Pruning a Mock Orange
Mock orange is an old-fashioned favorite with its large white, fragrant flowers blooming in late spring. Hardy in zones 4-9, most varieties mature to a height of 6-8 feet (2-2+ m.) and have a natural vase shape. With a just little maintenance, a mock orange shrub can be a beautiful addition to your landscape for many years.
Before pruning any plants, you should always sanitize your pruners or loppers to prevent the spread of pests and diseases. You can simply do this by wiping the tools down with a mixture of bleach and water or rubbing alcohol and water. Be sure to get the cutting surfaces of the tools.
If you are pruning a mock orange because it is infected by a pest or disease, dip your pruners in water and bleach or rubbing alcohol between each cut to avoid the risk of further infection.
Mock orange blooms on the previous year’s wood. Like lilac, mock orange bushes should be pruned right after blooms have faded, so you do not accidentally cut off next year’s flowers. Since mock orange blooms in late spring to early summer, they are usually cut back once a year in late May or June.
It is recommended that mock orange shrubs not be pruned or deadheaded after July to ensure blooms the next spring. However, if you just purchased and planted a mock orange, you should wait until the following year before doing any deadheading or pruning.
How to Trim Mock Orange
Pruning a mock orange each year after it blooms will keep the plant healthy and looking good. When cutting back mock orange shrubs, cut back the branches with spent bloom about 1/3 to 2/3 their length. Also, cut out any old or dead wood back to the ground.
Branches that are crowded or crossing should also be cut to open up the center of the plant to air, sunlight and rain water. When pruning anything, always discard the cut branches immediately to avoid the spread of pests and disease.
In time, mock orange shrubs may get gnarly looking or become less productive. If this happens, you can give the whole shrub a hard rejuvenation pruning by cutting it all back to 6-12 inches (15-30 cm.) from the ground. This should be done in winter or early spring while the plant is still dormant. You most likely will not get any blooms that spring, but the plant will grow back healthier and provide blooms the following season.