Mock orange (Philadelphus coronarius) is a deciduous shrub (it loses its leaves in the fall) that has a dense, rounded growth habit. It sports oval, serrated, dark green leaves. And it features showy, cup-shaped, four-petal flowers in the late spring and early summer that stretch roughly 1 to 2 inches across. These flowers are very fragrant, which is the primary reason many gardeners grow this shrub. The flowers are said to resemble orange blossoms, which is how the shrub got its common name of mock orange. They are rich with nectar that attracts butterflies and other pollinators. Mock orange shrubs have a fairly quick growth rate and can gain around 2 feet per year. They are best planted in the early fall but also can be planted in the spring.
|Common Name||Mock orange, mock orange shrub, sweet mock orange, English dogwood|
|Botanical Name||Philadelphus coronarius|
|Mature Size||10–12 ft. tall and wide|
|Sun Exposure||Full, partial|
|Soil Type||Loamy, moist, well-drained|
|Soil pH||Acidic, neutral|
|Bloom Time||Spring, summer|
|Hardiness Zones||4–8, USA|
Mock Orange Care
Mock orange shrubs are at their most attractive in the spring. Unfortunately, they do not have much to offer during other times of the year and are not ornamental enough to qualify as specimen plants. But they can be planted in groups to form a loose privacy hedge for summer, and their blossoms are often used as cut flowers. Just make sure their planting site has good drainage, as being waterlogged is not something these shrubs can tolerate.
Maintenance is generally very simple for mock orange shrubs. They don’t often have issues with pests or diseases. And established shrubs will only need watering during periods of drought. Plan both to fertilize and prune your shrub annually.
These shrubs can grow in full sun to partial shade, meaning at least roughly four hours of direct sunlight on most days. They will generally bloom more profusely when planted in full sun.
Mock orange shrubs like organically rich soil. They can tolerate a wide range of soil types—including sandy, clay, and loamy soils—as long as they have good drainage. Moreover, they do best with an acidic to neutral soil pH.
These shrubs prefer moist but not soggy soil. They do have some drought tolerance once they’re established, but don’t let the soil completely dry out on them. Water mature shrubs during periods of drought, and water young shrubs to keep the soil lightly moist.
Temperature and Humidity
Mock orange shrubs are hardy to the cold weather within their growing zones and typically don’t need winter protection. They will appreciate some extra water and protection from harsh afternoon sun in excessive heat. Humidity typically isn’t an issue for these plants.
Mix some compost, bark humus, or manure into the soil when planting mock orange. Then, for annual feedings in the late spring, add a layer of compost around the shrub, working it into the soil. Do not use a nitrogen-rich fertilizer. It can significantly increase leaf growth, which can hinder or even stop blossom growth.
Types of Mock Orange
The fragrance is a major selling point for mock orange shrubs, but not all varieties are equally fragrant. Therefore, a good time to purchase is when the shrub is in bloom at the nursery, so you can smell before you buy. Note that the flowers are most fragrant in the evening. There are many varieties of mock orange shrubs, including:
- 'Aurea': This variety is more compact than the main species plant, growing around 5 to 6 feet tall and wide, and it sports gold foliage in the spring.
- 'Blizzard': Particularly tolerant to cold weather, this variety only reaches around 5 feet high by 3 feet wide.
- 'Miniature Snowflake': This variety only grows to around 3 feet tall by 2 feet wide but produces especially fragrant double flowers (having extra petals).
- 'Snowbelle': Fragrant double flowers adorn this variety, which only grows to around 4 feet tall and wide.
- 'Variegatus': This shrub reaches a maximum height of 6 feet and sports white and green variegated foliage.
Mock orange shrubs bloom on the prior year's growth. Therefore, to avoid missing out on flowers for the next year, prune the shrubs immediately after they're done blooming. On stems that have just finished flowering, prune off growth above where you see outer-facing buds. Also, prune off any dead, damaged, or poorly shaped branches.
As mock orange shrubs mature, they can become somewhat overgrown. At that point, you can cut the oldest one-third of the branches down to ground level at the time of your annual pruning. After three years of such pruning, the shrub should look healthier. For severely overgrown shrubs, prune all the branches to the ground in the spring. You won't enjoy blooms that year. But this rejuvenation pruning will soon have healthy new branches popping up from the shrub's base.
Propagating Mock Orange
Rather than purchasing a nursery plant, a much more cost-effective way to get a new mock orange shrub is by propagating via cuttings. Taking cuttings is best done in the summer when the shrub is actively growing. Here's how:
- Fill a small pot with a fast-draining seed-starting mix. Make sure the pot has drainage holes.
- Using sterile pruning shears, cut a piece of branch that's roughly 5 inches long just below a leaf node.
- Remove the leaves on the lower portion of your cutting, leaving at least two sets of leaves.
- Apply rooting hormone to the cut end of your branch.
- Bury the cut end in your growing medium. Moisten the soil, but do not make it waterlogged.
- Keep the pot in bright, indirect light, and make sure the soil stays lightly moist. Roots should form in about a month. When you feel resistance when you gently tug on the stem, you'll know the cutting is ready to be transplanted to your desired growing site.
How to Get Mock Orange to Bloom
Mock orange flowers are the star of this plant. The four-petal white flowers generally bloom in May and June in numerous clusters of five to seven, and they have a very sweet scent. They will readily rebloom year after year as long as the shrub remains healthy and in optimal growing conditions.
Adequate sunlight is a key factor in getting this shrub to bloom profusely. Full sun is best, meaning at least six hours of direct sunlight on most days, though the shrub also can live in slightly lower light conditions. Moreover, pruning out roughly a third of a mature shrub's oldest branches will encourage new and more vigorous stems to grow, which in turn should produce more flowers. It is not necessary to deadhead the flowers (remove spent blooms).
Common Problems With Mock Orange
Mock orange is not known to have many problems when grown in the proper environment. However, inadequate growing conditions or care can result in some common issues.
Improper pruning is a common culprit for mock orange shrubs that aren't blooming well or at all. Be sure to prune immediately after your shrub is done flowering for the season. Otherwise you run the risk of pruning off the flower buds for next year. Also, check your shrub's environmental conditions. If you're using lawn fertilizer near your shrub, you might accidentally be giving it too much nitrogen. A soil test can tell you whether the soil around your shrub is too high in nitrogen.
Leaves Turning Yellow
Yellowing foliage on a mock orange shrub is often a sign of overwatering. While this shrub likes moist soil, it does not do well when waterlogged. Make sure your soil is draining well, and try putting a little more time in between waterings.
Can mock orange grow in shade?
Mock orange can tolerate partial shade but not full shade. The more light it gets, the better its flowering will be.
Is mock orange easy to care for?
Mock orange is a low-maintenance shrub. It typically requires watering during periods of drought and annual feeding and pruning.
How fast does mock orange grow?
Mock orange has a fast growth rate, gaining around 2 feet per year on average.
Why Plants Fail to Flower or Fruit. Clemson University Cooperative Extension.