Purple snow

Sunday, 25 October 2009

Jacaranda mimosifolia

In a cute children's book by Eric Löbbecke, a cockatoo regards a carpet of fallen Jacaranda blooms as 'purple snow', and this is the closest my Sydney garden will ever get to having a cover of snow. The arrival of the flowers of this tree in late October each year evokes in me simultaneous emotions of anxiety and joy. My dread comes from the fact that its blooming season heralds the annual school and university examination period, so due to some sort of Pavlovian conditioning, I feel slightly queasy at the sight of those lilac bells, even though I haven't done an exam for nearly 30 years. A specimen grows within the main quadrangle of Sydney University, which we always thought had been planted as a sort of horticultural warning to students of when to start studying furiously!

But the delight comes from being able to enjoy the flowers of a truly quintessential Sydney tree, which represents to me what we gardeners can grow in our mild climate. We have one of the best climates in the world in which to grow Jacaranda (outside of its native home of Brazil) - it doesn't like very cold areas or very hot equatorial climates, so ours is just right. Journeys around Sydney at this time show a city simmering in an amazing purple haze.

Jacaranda mimosifolia

Jacaranda mimisifolia belongs to Bignoniaceae, the Bignonia family, which contains many of the (often vigorous) climbers that we enjoy in our gardens. The various native species of Pandorea which are just starting to bloom, and Clytostoma callistegioides, which has just finished, are some of the more restrained ones. The characteristic flowers of the family are large and tubular, with flaring mouths. The Jacaranda has mauve-blue foxglove-like blooms, held in large panicles. There are white cultivars around, but to me that defeats the purpose of growing the tree in the first place. The tree has finely divided, fern-like foliage, and grows to a height of 12-15m, forming a broad dome, making it very useful as a source of summer shade.

The foliage is shed around August, then reappears in late November or early December. The dramatic appearance of the flowers is best on trees where the leaves come after flowering rather than at the same time: this seems to vary from one tree to the next and is also possibly a climactic phenomenon. The bark has a lovely elephantine texture, and the tree is best left unpruned, once it has been trained to a single main trunk, as often ugly vertical shoots will arise from the points at which it is cut. It likes a sunny, well-drained position in the garden.

Fallen Jacaranda petals

The down side of the tree is that it will often self-seed via its woody rounded seed pods, so you need to be vigilant in removing baby seedlings, unless you want a forest of Jacaranda. It does need a bit of space, so is not suited to very compact gardens. It is also difficult to establish garden beds nearby to the greedy, shallow roots of the tree. But I would never want to be without one of these trees in my garden. When the lawn is smothered with the fallen petals, it is one of the highlights of our Sydney gardening year!