pronounced: tib-OO-chee-nuh joulz
Tibouchina is from the native name for the plant. The genus occurs naturally in the rainforests of Mexico, the West Indies, and South America, particularly in Brazil, where the masses of purple blooms of Tibouchina are used to decorate the churches at Easter. This cultivar, a dwarf variety, was developed at Alstonville, NSW, by the late Ken Dunstan. The genus will grow in most parts of Australia, but is not suited to cool mountain districts or inland areas. It also needs protection against frosts, and against strong winds – the square stems are rather brittle. A line of ‘Jules’ was planted along the fence at the rear of the Dunoon development in Picnic Bay, but the garden there has since been replaced by a row of palms.
‘Jules’ is a dwarf evergreen shrub that grows to about 1 m high and 1– 2 m wide. It has small velvet green leaves, and purple flowers from March to May. The 5-petalled blooms are open and flat, with prominent stamens that reach out from the centre. When not in flower, the foliage of these shrubs provides attractive background texture. ‘Jules’ grows happily in tubs as well as in garden beds.
The story of Tibouchina in Australia began in the 1960s, when some seed was imported. The Dunstan family, mentioned above, were probably most instrumental in popularizing the genus, developing a number of cultivars. In Ken Dunstan’s time, an annual Tibouchina festival was held in Alstonville, NSW, where their nursery was located. Many of the varieties grown in Australia are large shrubs or trees. Most of them do best in acidic soils. If the soil is not acidic enough, the leaf burns at the edges, turns brown, and eventually dies. The soil acidity can be increased by adding sulphur to the soil around the roots, or by using an acidifying fertilizer.
The larger varieties do need pruning, or they will grow quite large and rather straggly. Any pruning is best done immediately after the flowering season. Delaying the pruning throws the flowering cycle out of kilter, and results in spasmodic flowering. ‘Alstonville’, also developed by Ken Dunstan, is probably the best of the larger cultivars, and grows into a small tree up to 5 m tall. It puts on a brilliant display of blossom, and is eminently suitable as a specimen or a street tree.
So long as the soil acidity is right, and there is shelter from the wind, Tibouchina does well because it is resistant to most diseases and pests.
