Bulbine bulbosa (Native Leek)
Bulbine bulbosa is a perennial herbaceous plant, growing to about half a metre tall with a 30cm spread.
It’s a native Australian plant which strangely enough belongs to the Xanthorrhoeaceae family, the same family as the iconic native grass trees.
The native range of Bulbine bulbosa is restricted to the Eastern states of Australia including Tasmania and the eastern edge of South Australia. Over its range it can be found growing in a variety of habitats, although it seems to grow best in boggy spots.
Some of the common names for Bulbine bulbosa include Native Leek, Golden Lily, Bulbine Lily, Yellow Onion, Leek Lily and Yellow Onion Weed. Although the genus name Bulbine means bulb and the species epithet bulbosa means bulbous, the underground storage structure of Bulbine bulbosa is not a bulb at all, it’s actually a corm.
The underground corms of Bulbine bulbosa are rich in calcium and iron and were roasted and eaten by aboriginal people who regarded them as having the sweetest corms of all the lily-like plants.
Some of the indigenous names for this plant include Puewan, Parm (Gunditjmara name) and Pike.
Corms require several years of growth before they are of a decent size for eating.
All other parts of the plant except the cooked corms contain toxins and should not be eaten.
Use in the Garden
Aside from their edible use, Native Leeks are also quite attractive due to their bright yellow flowers each up to 3cm in diameter and having 6 petals. They flowers are borne on large spikes during mid Spring to mid Summer and are held above the foliage. They have a faint but pleasant, rose-like scent and can provide a lovely, meadow-like effect when planted en masse.
The leaves are a fresh vibrant green colour when they are actively growing, providing a nice contrast to the flowers. They are fleshy, cylindrical and hollow within like scallions (called Spring onions or green onions in some countries).
The leaves tend to die back in late Summer after which time the plant will become dormant until the leaves start to re-shoot from the underground corm during late Winter.
Bulbine bubosa is tolerant of frosts, but it won’t grow well in sandy coastal or desert gardens. During dry spells Native Leek will become dormant and the leaves will die back, although prolonged periods of drought will kill it. Water Bulbine bulbosa well when they are actively growing but reduce watering from Autumn to mid Winter when plants are dormant.
Plant Native Leek in full sun to achieve fastest growth in milder climates or in semi-shade in hotter areas.
While Bulbine bulbosa can self-sow in the garden, it’s unlikely to do this unless provided with an area to colonise free of other plants as the young seedlings are easily out competed by grasses, weeds and other plants.
If you want to grow a patch of Native Leeks from seed you should first prepare the soil to a fine tilth, then broad-cast the seed over the area, rake them in, firm them down and water well. Best results are obtained when the seed are sown from late Winter to early Spring. Germination takes around a month.
Adding a smoke extract to the water (to simulate the natural chemicals in the smoke of bushfires) has been found to increase the germination rate by about 10% for this species, although it’s only really required if you are having difficultly getting the seeds to germinate otherwise.
Corms can also be lifted and divided to propagate news plants during Autumn.