Friday, March 5, 2010


but not as we know it.
Auranticarpa rhombifolia
(Pittosporum rhombifolium)
It took me a moment to realise what this plant was, when I saw it at Irongate last weekend. Compared with the hollywoods we see in so many local gardens - many of which would be grown from local seed gathered along the range - its leaves are just a bit thinner, less stiff and a bit less shiny. The veins are more prominent on the upper side, and the leaves are much droopier. Each difference is trivial, but the overall effect is of a slightly different plant.
There is a lot of genetic variation within species of Australian plants. One of the good reasons for growing them from local seed - truly “indigenous” plants - is that they may be better suited to local conditions. I imagine that seed from this plant would be hardier to frost and drought, and more suitable for the sometimes very tough growing conditions on the Darling Downs. This was also a broader plant than the more familiar variety, and would make a really nice shady little tree, suitable for a suburban garden on the black soil on the western side of Toowoomba.
This specimen is flowering beautifully. I think of the species as spring-flowering, and around Toowoomba the hollywoods are starting to show their beautiful orange autumn berries already. (They’re going to be magnificent again this year.) So it surprised me to find this one flowering in late February. Perhaps all the hollywoods, even the garden varieties, have been late to flower out there, in those places which have largely missed out on out summer rainfall? Or perhaps this dry scrub version of the plant is also genetically better at opportunistic flowering. This kind of opportunism, where plants can put out flowers in response to rain rather than to the time of year, is a drought survival technique which we could actually expect to be better developed in plants that are adapted to life in dryer climate zones.
Pittosporum species (and this close relative) have the reputation of being some of the best natives for flower fragrance, and if you’re still reeling from the shock of the “perfume” of Parsonsia eucalyptophylla, try this one. It really is lovely.
(See my blogs, April 2008 and March 2009 for more on this species.)

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