July 28, 2022
Searles Gardening Team
If you love the colour of purple in the garden, then you'll just adore the magnificent flowering Tibouchina.
Tibouchina's are magnificent shrubs that are ideally suited to our tropical to sub-tropical climate. There are many wonderful varieties available that vary in size & colour from 1m shrubs to 6m trees, with deep purples & even pink and white flowers. There are some varieties that flower just about all year round, but their main flowering times are in the warmer months of summer to autumn & they look fantastic!
Tibouchina ‘Alstonville’ – The original Tibouchina, it takes its name from the small north coast NSW town of Alstonville where it was developed by the Tibouchina enthusiast Ken Dunstan. This small tree grows to about 5m to 6m in height and is covered in purple flowers. Perfect for ‘front of house’ planting.
Tibouchina ‘Little Beauty’ – Large purple bright purple flowers. Grows to a 1m H.
Tibouchina ‘Chameleon’ – As the names suggests the flower changes colour from pure white to all shades between to deep pink as the flower ages. This fast growing shrub grows to 2m H.
Tibouchina ‘Jazzie’ – Large deep purple flowers. Grows to 1.5m H
Tibouchina ‘Peace baby’ – White flowers with pink and purple stamens in its centre. Dwarf and compact variety, grows to 60cm H.
Cooler climate gardeners are now able to enjoy growing these beauties with the relative recent release of Tibouchina ‘Cool Baby’ and Tibouchina ‘Groovy Baby’. Additional benefits are their hardiness and at ease in producing large blooms on a compact canopy making them ideal for pots.
Tibouchina ‘Groovy baby’ – Purple flowers. The most compact variety, grows to 45cm H. Its hardiness makes them suitable to grow in cooler climates. Protect from heavy frosts though.
Tibouchina ‘Cool baby’ – Dense and compact variety. Covered by large pink and white flowers. Well suited for pots.
Now there are a few tricks for abundant flowering. Firstly, they need a good sunny position and like to be planted into a rich acidic soil. They don't like alkaline soils (those soils with a pH of 7 or above), but flourish in slightly acidic soils with a pH of around 5.5 to 6.5. If your soil is alkaline, the pH can be lowered by adding to the soil Sulphur Powder. Follow the directions on the container to suit your soil type. Alternatively you can plant straight into Azalea, Camellia & Gardenia Specialty Mix for both gardens and pots.
Tibouchinas like a warm to hot climate and don't mind some cool weather in winter, but they will be affected by frosts, so may not be suitable for those gardens that are frosted.
Fertilise Tibouchinas every autumn & spring with 5 in 1® Organic Fertiliser and also add a couple of handfuls of Searles Azalea & Camellia Plant Food. Then cover the soil with a thick layer of a high quality mulch, such as Searles Premium Garden Mulch, and then give them a good deep watering.
Watering: When first planting a Tibouchina, they will need regular watering until established, to ensure a good start to their life. Once they have established a good deep root system (after the first year), a good deep watering once a week should suffice. If you live in an area that receives a moderate to high rainfall, you may very well find that these beautiful shrubs will hardly need any additional watering at all.
Pruning: The real trick to promote profuse flowering for the next season is to prune them back hard immediately once the last flowers fall. This will encourage more new growth, helps to keep the foliage compact and results in more flowers.
Growing Tibouchinas is good fun and they require very little maintenance. They are an easy to grow plant, and when in flower, they are just stunning, decorating the garden with a lovely and profuse display of deep purple blooms.