Elaeocarpus angustifolius Seeds | Rudraksha Tree
LATIN NAME: Elaeocarpus angustifolius
COMMON NAME: Rudraksha Tree, Blue Marble Tree, Blue Quandong
Plant Profile
The blue marble tree is a rainforest tree of twenty to thirty metres with a straight trunk, glossy leaves that turn red before they fall, and small flowers followed by bright blue fruit the size of a marble. The fruit is eaten by birds and by cassowaries, and the seed inside is deeply pitted like a carved bead.
It grows from northern Australia through New Guinea to the Philippines and Indonesia, in lowland and foothill rainforest. The timber is pale and soft, and the tree is planted in parks in Queensland and in Singapore for the blue fruit that carpets the ground under it.
Science & Biotechnology
The seed is the hardest part of the plant and the slowest to germinate. The stone is thick-walled and the embryo dormant, and germination can take a year or more without treatment. In the wild the passage through a cassowary’s gut scarifies the coat, which is why the species regenerates along the paths the birds use.
The blue colour of the fruit is structural rather than pigmentary in part: the skin contains anthocyanins over a layer that reflects light, and the combination produces a blue that is unusually pure for a fruit. That colour is a signal to birds, which see it against the green of the forest floor. The timber is also unusual in being almost white and very light, and it is used for boxes and for pattern-making rather than for structural work.
Uses & Benefits
The seed is drilled and strung as a bead, and it is sold as rudraksha in India, though the true rudraksha of the prayer trade is Elaeocarpus ganitrus, a close relative with a larger and more deeply grooved stone. The two are confused in the market and the substitution is common.
The timber is used for light construction, for boxes and for veneer, and the tree is planted as an ornamental in tropical parks. The fruit is not eaten by people, and the bark is not used medicinally in modern practice, though related species are. The fallen fruit stains paving a deep blue, which is worth knowing before planting one beside a driveway.
Growing from Seed
Sow the cleaned stone in a moist, free-draining mix at twenty-five to thirty degrees. Expect a long wait: germination is erratic and may take six to eighteen months, and the seed should not be allowed to dry out. Crack the outer shell carefully if you want to shorten it.
Plant out in a frost-free climate in deep, moist soil, in sun or light shade, and water through the first two dry seasons. The tree needs humidity and does not tolerate drought or salt wind. In a container it grows slowly and is best treated as a foliage plant until it can go into the ground.
Our Take
A blue-fruited rainforest tree with a bead for a seed, and one that needs a warm climate and a lot of patience. Not the true rudraksha, though it is sold as such.
Related Reading
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