GINA PARKINSON looks at the way milder winters are changing the plants we can grow.

MILDER winters allow gardeners to look at growing plants usually considered to be tender. Such plants now stand a good chance of surviving permanently in the garden.

One such specimen is the Pittosporum, an evergreen family of shrubs and small trees mainly from Australasia. Hardy in mild and seaside areas, they will also cope with colder weather in the north if they are grown in a sheltered spot by a warm wall, preferably in full sun with well drained soil.

The most popular Pittosporum is P.tenuifolium, a slow-growing shrub that will eventually grow four metres high with black twiggy branches covered in wavy edged pale green leaves.

In mild coastal areas it is often grown as a hedge, while flower arrangers will grow it to harvest the attractive stems and foliage for their arrangements.

There are numerous cultivars of this species including Silver Queen with narrow, silver grey leaves tightly bunched on the dark stems, Wendle Channon with yellow edged dark foliage and Warnham Gold with yellow or yellow-green juvenile foliage that ages to gold.

Tom Thumb is, as its name suggests, smaller growing, eventually reaching around a metre in height and spread and forming a compact, dome-shaped bush. New leaves are pale green but they quickly darken to deep purple, making it an interesting addition to the garden, perhaps against a wall in a narrow bed or in a container on a sunny patio.

In his book Shrubs Through The Seasons, plant hunter and horticulturist Roy Lancaster describes seeing Pittosporum tenuifolium growing wild in New Zealand, where it is common in coastal and lower mountain forests and scrublands on both islands.

In this situation it produces small, chocolate-purple coloured flowers with a strong honey fragrance especially in the evenings, although in the UK blooms are rarely seen.

The tall growing variety Irene Paterson was found in the wild near Christchurch by Mr G Paterson, while another tall variety James Stirling was raised in New Zealand by James Stirling in 1966.

Irene Paterson has young white leaves that become densely speckled with green and grey green, while James Stirling has very small, pale green rounded foliage.

If Pittosporum flowers are wanted it is best to grow the Japanese or tobiri pittosporum, Pittosporum tobira. This originated in China, Japan and Taiwan but is now seen in southern Europe and in favourable areas further north.

It needs a mild climate but like other members of the family is worth trying by a sheltered south or west facing wall.

The leaves of this shrub are large, glossy and bright green and cream coloured, orange-blossom scented blooms are carried in mid summer. P.tobira variegatum has irregularly variagated leaves with cream margins and central patches. It is more tender than the species.

Pittosporum planting details...

SITE. Warm and sheltered in full sun or light shade, preferably by a wall. It can be grown as a wall shrub and will tolerate salty, coastal air but not desiccating wind.

SOIL. Well drained. Cold, winter wet soil can be fatal.

PRUNING. Not needed but can be cut back in spring if required. Most will grow from old wood so can be cut hard back if necessary.

PROPAGATION. From semi-ripe cuttings taken in early summer.

Updated: 07:30 Saturday, November 22, 2003