Tuesday, December 9, 2008


Most of the spring flowers have nearly finished, and much of the bush and garden shuts down for midsummer. The heat and drier conditions mean plant leaves tend to close their leaf pores (stomata) to conserve moisture, but they then reduce respiration, reduce carbon dioxide uptake, and so slow right down. Summer wattles are an exception, and there is another burst of gold due around Christmas.

However, there are two special flowerings here this month. The Dorrigo Waratah (Alloxylon pinnatum) is a medium sized tree, naturally found in temperate rainforest areas. It is happy here provided with extra summer water, well mulched, and talked to daily. They know what you say. It has exceptionally beautiful terminal flowers, a little like symmetrical grevilleas, a whorl of deep scarlet petals which unfurl gradually, the tips getting a cyanotic blush as they mature. We have grown them for the export market, but this year are giving them, and us, a break.

Alloxylon pinnatum

More familiar is the Flannel Flower (Actinotus helianthi), found growing wild on sandy coast dunes around Sydney, and even quite rampant on Middle Head. It is, for many, the most beautiful of our native flowers, perhaps because it has a traditional European look and is at the same time hardy but delicate looking. The creamy off-white 'petals' (actually they are bracts, there are no true petals) have a soft flannel feel, with a tip of faded olive green at each point. Each plant has a life of about 4 years, but in the right conditions they seed prolifically.

Actinotus helianthi

Both these plants have something unusual in common with us. They are subject to air embolism, whereby in abnormal circumstances, an exposed vascular system, at least that under low pressure (veins) can entrap air. Where there is air, there's no blood: no blood, no oxygen, no oxygen...

In these flowers, cut them and they may not bleed, but cut them and they 'suck' air into their vascular system, the ingenious method of their getting water and nutrients uphill, and the outcome is wilting and reduced vase life. They need to be picked into water, and how hard is that? Very hard.

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