Native to Asia, especially in Japan, China, and Korea, Pittosporum tobira [pit-oh-SPOR-um TOH-bir-uh] is a dense mounding evergreen shrub belonging to the Pittosporum family (Pittosporaceae).
Despite its nativity to Asian countries, it has been naturalized in many other areas.
It is used around the world as an ornamental plant for landscaping and in floriculture or flower farming for their inflorescences fragrant flowers.
The name Japanese Pittosporum tobira is a reference to two aspects of the plant type.
Pittosporum means resinous seeds and is a reference to the Mock Orange’s black seeds which are contained inside the fruits in resinous pulps.
Tobira, on the other hand, is derived from the Japanese name of the fruit.
Common names include:
- Australian laurel
- Japanese pittosporum
- Mock Orange
- Japanese cheesewood
Pittosporum Tobira Care
Size & Growth
When grown in the right climate and growing conditions, the sweetly-fragrant Mock Orange plants can grow up to 10′ feet tall and about 3’ feet broad.
They’re small tree-like but are easily trimmed down to a hedge.
The plants are evergreen and have lush dark green year-round foliage of leathery, glossy leaves.
The leaves are around 4” inches long, oval and have edges which curl underneath them.
They create a striking contrast when the small white flowers bloom and scent the air with a citrusy fragrance.
Flowering and Fragrance
Pittosporum tobira ‘variegatum’ plants get this common name from the flowers, bloom time is in late spring to early summer.
The showy whorls of inflorescences are reminiscent of a sweet orange blossom fragrance is very attractive to bees and butterflies alike.
These flowers appear as clusters at the end of branches, surrounded by leathery, hairless green leaves.
The flower color is white with 5 petals.
These creamy white flowers are about a ¼ inch long.
The plants also produce fruits appearing as hairy, woody capsules divided into three valves.
Each fruit is a ¼ inch wide and contains black seeds in a resinous pulp.
Light & Temperature
Japanese Cheesewood plants are attractive evergreens hardy to hardiness zones 9 – 10 (USDA zones).
Within these zones, the plants can thrive in full sun to part shade.
If you are planting Mock Orange plants indoors, in containers, it is best to place them in bright light, but avoid direct sunlight.
They can tolerate temperatures down to 14° degrees Fahrenheit (-10° C) but do well in warmer climates.
However, high heat and high irradiance from western exposure in the summer can cause damage.
Watering and Feeding
During the summer, when the soil tends to dry out quickly, water Mock Orange plants regularly.
Even though they are drought-tolerant, they thrive in medium moist soil.
But be cautious about overwatering as constantly wet soil tends to cause root rot.
Reduce water needs in the winter.
Japanese Mock Orange plants have moderate requirements for fertility.
Use a fertilizer occasionally if your soil is poor in nutrients.
However, you will get away with not fertilizing if the soil is well-drained and rich already.
Soil & Transplanting
Mock Orange plants are not very picky when it comes to soils.
They can thrive in moderately rich and average soils, meaning they’re often planted in chalky, sandy, and loamy soils.
Slightly acidic pH will be preferred, but neutral soil is also tolerated.
The plants do love moist soil, but not too much.
So make sure whatever soil you use, it is well-drained.
When transplanting seedlings, prick them from the cold frame when they are long enough to be handled and then place in individual pots in moderately-rich, medium moist, and well-drained soil.
Place it in a greenhouse during the winter and then transplant in the ground in a sunny location.
Grooming and Maintenance
Mock Orange plants don’t have high-maintenance needs.
The plants don’t require any pruning.
They can get spoilt by hard pruning and are hence fall into the RHS Pruning group 1 in the UK.
However, head back to control size or use the extensive renewal pruning method to improve overgrown species.
But be sure to never shear Mock Orange plants as it may stunt their growth.
How to Propagate Mock Orange
When propagating with seeds, sow them in the fall or late winter once the seeds are ripened.
The seed will germinate freely, provided they are kept in a warm greenhouse during the winter.
Once the seedlings have established, plant them in individual pots and move them to a cold frame.
Plant them outside the following spring and provide shelter when the second winter rolls around.
If you’re using softwood cuttings, take 1.5” – 2” inch cuttings and plant in a cold frame during July or August.
There is a fifty-fifty chance of the cuttings to succeed.
Mock Orange Pest or Disease Problems
These pests are easy to deal with and are treated with simple pesticides like white oil.
Other than these, Mock Orange can get cotton cushiony scale, pit-making pittosporum scale, and root-knot nematodes.
Consult your local botanical garden or nursery to find out if these are causing damage to your plant and then ask for advice for treatment.
When it comes to diseases, Mock Orange is vulnerable to a fungal pathogen called Erythricium salmoni color.
This particular fungal infection appears as galls. It can cause dieback disease called pink limb blight.
Suggested Mock Orange Uses
Mock Orange plants are very versatile when it comes to their use.
They are very popular in landscaping and are planted in both beds and borders in all sizes of gardens.
In China, Japan, and China, the plants are placed in pots and used for ornamental purposes outside of buildings.
The sweet citrusy scent of the Mock Orange flower is also popular in floriculture.
The plants are cultivated in large quantities to be used for decorative purposes and as cut flowers.
Similar to Boxwood, the Mock Orange plant is used as a wind-resistant hedge in areas where there is maritime exposure.
They are often used in shelterbelt plantings.