<em>Pittosporum</em>: planting, growing and pruning

Description and botany

Genus Pittosporum, belonging to family Pittosporaceae, comprises about 200 species, mostly from New Zealand, Australia and New Caledonia, such as Pittosporum tenuifolium. Pittosporum tobira is native to Japan and China.

Pittosporums can reach up to 20 m or more in native regions. Under our latitudes, cultivated varieties rarely exceed 3–4 m. Dwarf, compact varieties also exist, such as Pittosporum tobira ‘Nanum’, ideal for creating low hedges. Pittosporum’s also makes it easy to train as topiary, making it a good substitute for box.

Size and shape of leaves vary greatly depending on species or variety. Some, like Pittosporum tenuifolium, have small, round, leathery leaves no longer than 3–4 cm, while others such as Pittosporum heterophyllum bear more elongated leaves up to 8 cm long.

Pittosporum tobira – botanical illustration

Foliage diversity among Pittosporums goes further, with many colour variations. Varieties with glossy green leaves sit alongside those with golden, purple or variegated foliage. Pittosporum tenuifolium ‘Elisabeth’ is one of the most striking, with leaves edged in white that turn red as seasons progress.

All Pittosporum species and varieties flower in spring, between May and June. White, yellow or even purple flowers, their flowering diversity matches that of their foliage. Even the most discreet blooms emit a strong fragrance reminiscent of orange blossom. Flowering is followed by capsule-shaped fruits that split at ripeness, revealing waxy red seeds. These seeds can be easily harvested for sowing under a cold frame.

Not very hardy, it nevertheless tolerates pruning very well and resists sea spray, making it an ideal bush for coastal sites or a dry Mediterranean-style garden. In regions with severe winters, particularly those subject to a montane climate, favour Pittosporum heterophyllum, one of the hardiest, or opt for planting in pots.

Pittosporums grown in pots can be overwintered easily in a bright, very lightly heated room, such as a conservatory.

Pittosporum tobira : foliage, flower buds, flower and fruits.

Species and varieties

Most popular varieties

Varieties to discover

Pittosporum tobira

Hardy to -5°C, this compact bush has glossy evergreen foliage, ideal for creating a seaside hedge. In May it is covered with white bells exhaling an orange blossom scent. Available in dwarf form (Pittosporum tobira ‘Nanum’).

• Flowering time June
• Height at maturity 5 m

See the product sheet

Pittosporum tenuifolium Irene Patterson - Kohuhu

Originality of this small bush with a very compact habit lies in its foliage speckled with white and green, often tinged pink in winter. Contrast is all the more striking as both stems and flowers display a purplish-violet hue.

• Flowering time June, July
• Height at maturity 1,50 m

See the product sheet

Pittosporum tenuifolium Elisabeth - Kohuhu

This Pittosporum stands out for the beauty of its evergreen, variegated foliage that changes colour through the seasons. Variegated grey-green and cream-pink in spring and summer, the leaves gradually take on pink and red tones in winter.

• Flowering time June, July
• Height at maturity 2 m

See the product sheet

Pittosporum tenuifolium Variegatum - Kohuhu

Hardy to -7°C, this bush bears elegant foliage marginate with white-cream and a discreet but fragrant flowering. It adapts well to being grown in pots, and is also used in seaside hedges.

• Flowering time June
• Height at maturity 2,50 m

See the product sheet

Pittosporum heterophyllum

This evergreen bush stands out for the intense scent released by its spring flowering, a blend of honey and vanilla. It is one of the hardiest species (to -10°C), but requires well-drained soil.

• Flowering time June, July
• Height at maturity 2,50 m

See the product sheet

Pittosporum tenuifolium Abbotsbury Gold - Kohuhu

This pittosporum is arguably one of the brightest with its black branches that contrast with evergreen variegated leaves of very bright green and yellow. In spring delicate scented flowers emerge, of an exquisite blackish-purple.

• Flowering time June, July
• Height at maturity 2,50 m

See the product sheet

Planting Pittosporum

Where to plant it?

Moderately hardy, Pittosporum generally does not tolerate frosts below 7°C. Planting in open ground should therefore be reserved for regions with mild winters such as the Mediterranean or Atlantic coast. Preferably give it a warm, full-sun position. A partly shaded position is possible for some varieties, such as Pittosporum tenuifolium ‘Variegatum’, but the bush will grow less and will be less compact.

In regions with a montane climate (Pyrenees, Alps, Massif Central, Jura…), favour a species offering good hardiness, such as Pittosporum heterophyllum, and install it sheltered from the wind, for example against a south-facing wall. You can also opt for container cultivation, bringing it indoors over winter.

Although Pittosporum is not very demanding about soil type, avoid very calcareous soils and heavy soils that retain moisture. This bush therefore needs good soil drainage to develop. It would rather have soil that is on the dry side than waterlogged, and preferably soil relatively rich in organic matter.

Compact varieties, notably Pittosporum tobira ‘Nanum’, can be grown in pots. They can thus be brought indoors during winter in climates experiencing severe frosts.

When to plant Pittosporum?

Prefer planting in spring, between March and April, or failing that in autumn, between September and October.

How to plant it?

Once your location is chosen:

1. Dig a hole two to three times the size of the rootball.
2. Mix your garden soil with leaf mould and coarse sand to 50%.
3. Position the Pittosporum in its spot, leaving the collar (junction between roots and soil) level with the surface.
4. Backfill with the mix and firm down.
5. Water immediately and generously.
6. Mulch around the base to help keep the soil cool.
7. Water regularly afterwards to favour establishment, once or twice a week.

For a hedge, space each Pittosporum plant about 1 m apart.

For container planting, use a substrate composed of equal parts garden soil, coarse sand and compost or potting compost. Improve drainage by placing a layer of gravel or clay balls at the bottom of the pot.

Delicate inflorescences of Pittosporum heterophyllum, with fragrance reminiscent of orange blossom.

Care

Pittosporum can tolerate dry soil. However, to ensure optimal development, we recommend watering it once a week during summer.

This precaution is especially necessary for plants grown in pots, as this method of cultivation encourages evaporation of moisture from substrate. Also give them a monthly liquid feed during growth (March to September).

In autumn, mulch around base to protect roots of your Pittosporum from frost. If exposed to cold winds, protect foliage with winter fleece.

Potted plants can be brought into a bright, frost-free room, such as an unheated conservatory. Reduce watering to once a month to prevent substrate drying out completely.

Apply compost in autumn or winter to encourage beautiful spring flowering.

Pruning Pittosporum

Pruning Pittosporum is not essential but helps maintain an airy, harmonious habit. It should be carried out in mid-summer (late July), after flowering has finished. Pruning in early spring is possible but removes flowering, so we do not recommend it if you wish to enjoy its sweet fragrance.

Trim tips of shoots to even them up. Remove branches growing inwards as well as dead shoots. You can also prune it into a topiary.

In a pot, as growth is slower, stick to light pruning to rebalance the habit of your Pittosporum if needed.

Virginie T. tells you more in the tutorial How to prune Pittosporum?

Diseases and parasitic organisms

Pittosporum shows good resistance to disease. However, it can suffer mealybug infestations, especially in late spring or early autumn, when air is warm and humid.

These sap-sucking insects feed on plant sap, hindering development. Their presence can lead to sooty mould forming on leaves. This black deposit prevents photosynthesis, which also harms Pittosporum’s growth. Moreover, it is simply disastrous aesthetically.

For prevention as well as treatment, we recommend avoiding use of pesticidal products in favour of a natural method. For example, spray a mixture of liquid black soap, methylated spirits and vegetable oil. Repeat every 8 days.

Be aware, there is no miracle cure to guarantee eradication of mealybugs. Constant vigilance is your best ally, along with good growing conditions.

Variegated foliage of Pittosporum tenuifolium ‘Elisabeth’ changes colour through seasons.

Multiplication

Pittosporum multiplies easily by propagation by cuttings or sowing. Prefer propagation by cuttings, however, as it is faster and easier to carry out and will reproduce your favourite variety identically.

Sowing

Sowing Pittosporum seeds gives good results. However, patience is required, growth of these bushes is rather slow.

• Harvest seeds at ripeness, when red capsules split in late autumn.
• Sow directly in cold frame.
• Provide bright exposure without direct sun.
• Keep soil slightly moist.

First seedlings should appear within 30 to 60 days.

Seeds of Pittosporum tobira.

Propagation by cuttings

Propagation by cuttings of Pittosporums is carried out in summer, in July–August. Take cutting from a semi-lignified shoot, that is, one beginning to take on the consistency of wood but still flexible.

• Cut stems of about 15 cm at tip of semi-lignified shoots.
• Plant them in pot, in light substrate such as sowing compost. Keep moist.
• Place under cover, covering pots with half bottles or transparent plastic bags.
• Pot on into new pot when new leaves appear (may take several weeks).
• Keep cuttings between 5 and 10°C during winter.
• Plant out in autumn.

Associations

In mild climate, Pittosporum is well suited to creating free-form hedges. Feel free to vary colours by pairing bright green of Chinese Pittosporum (Pittosporum heterophyllum) with golden foliage of Pittosporum tenuifolium ‘Abbotsbury Gold’. Pittosporum can also mingle with other Mediterranean bushes such as oleanders or elaeagnus. Keep one metre between plants to allow them to thrive.

An idea for a free-form hedge association for mild climate : Nerium oleander / Pittosporum heterophyllum / Eleagnus ebbingei / Pittosporum tenuifolium ‘Abbostbury Gold’.

Use smaller varieties, such as Pittosporum tobira ‘Nanum’, to perfume paths with their delicate scent. Pair them with other aromatic plants (lavender, rosemary…) to enhance olfactory pleasures, or with other bushes for low hedges such as abelias. They also add structure to a rockery or can be grown in pots to adorn a terrace or balcony. Their compact habit makes them easy to train as topiary. Pittosporum is a worthy replacement for boxwood.

Pittosporum adapts well to container growing: Pittosporum tenuifolium ‘Emerald Gold’ / Pittosporum tobira ‘Variegata’.

If looking for a specimen capable of becoming a true focal point in a Mediterranean garden, opt for Pittosporum tenuifolium ‘Irene Patterson’. Its silver-speckled foliage provides a constant spectacle, particularly striking in spring when purple flowers appear, and equally delightful in winter when leaves take on a delicate pink tinge.

Finally, Pittosporum is an ideal bush for structuring a border or providing a dense, elegant backdrop. For best effect, vary shapes, habits and heights, and plant not in a straight line but staggered for a more natural result.

An example of a contrasting association in a border : Pittosporum tenuifolium ‘Tom Thumb’ / Tiarella cordifolia / Ophiopogon planiscarpus ‘Nigrescens’.

→ also read : Pittosporum: 5 ideas for successful plant combinations