Murraya paniculata

Murraya paniculata, also known as Chinese boxwood, is a highly floriferous evergreen shrub of Asian origin, belonging to the citrus family, from which it owes the powerful fragrance of its flowers. In tropical regions, it forms a large shrub with a rounded habit, but it will remain smaller in gardens of the most protected areas. Not very hardy, it is sensitive to frost and can be grown in containers almost everywhere. Its small, highly fragrant flowers have a short lifespan but bloom repeatedly over a long period. It should be grown in full sun and regularly watered, and should be brought indoors before the first frost.

The Chinese boxwood belongs to the Rutaceae family, which includes more than 150 genera, including the large group of citrus trees, as well as common ornamental plants such as Choisya ternata (Mexican orange blossom). Murraya paniculata is native to tropical Asia, and its natural range has expanded via Malaysia to Australia and the southwestern Pacific islands. In these regions, it grows in mountain forests from sea level up to 1300m (4265ft) altitude. It forms a large shrub up to 6m (20ft) tall, or even taller, and commonly blooms from April to October in successive waves. The extremely fragrant flowers only last for one day; the petals fall in the early morning.

Murraya paniculata is a beautiful evergreen plant with highly decorative foliage all year round. Its growth is quite rapid at first, but slows down in the following years. The branches have a pale grey to grey-white bark, which tends to peel off on the main axis as it ages. The compound leaves are alternate and odd-pinnate, with 3 to 7 or 9 ovate to elliptical leaflets, measuring up to 10cm (4in) in length. Dark green in colour, their surface is glossy, as is the case with many other Rutaceae. This dark mass of vegetation provides a backdrop for the pure white flowers, which stand out clearly. The small flowers, about 3cm (1in) in diameter, have corollas composed of 5 oval to lanceolate petals, resembling those of citrus trees. They are of the 5-type, and have 5 small sepals and 10 white-yellow stamens. The flowering lasts for several months, from spring to summer, with successive waves of blooms. Highly fragrant, they diffuse a delicious citrus scent. They then develop into small pear-shaped fruits that are orange to red in colour.

Its tropical origin makes it less hardy. It can withstand brief cold spells of around -2°C (28.4°F), which limits its outdoor cultivation to the mildest areas. It will then form a much smaller shrub, only 2 to 3m (7 to 10ft) tall, with a slightly narrower width, and a rounded and somewhat erect habit, well suited for hedges. 

In the garden, Murraya paniculata can be paired, for example, with Boronia heterophylla 'Carousel', a charming Australian shrub with bright pink flowers, or with Galvezia speciosa, a shrub with bright red tubular flowers. On the patio or balcony, it can be surrounded by Plumbago auriculata, which has a long flowering period and stunning sky blue flowers, or by Solanum rantonetti, with its long-lasting violet flowers with yellow centres. It is also possible to train this plant as a bonsai, as its leaves and flowers lend themselves well to a reduced size.