Aquatic edible plants

Water features are a key part of the edible foodscape in Dr Ketah Silvester’s subtropical Brisbane garden, on Yuggera Country. They yield delicious salad greens year-round while also attracting predatory insects, providing habitat for native animals, and enhancing the garden’s microclimate. Many people love taro or water chestnuts, which are both aquatic edible plants, but for Ketah and her family it’s all about aromatic herbs and leafy salad greens.

NATIVE RIVER MINT (Mentha australis)

This aromatic herb is a native of eastern Australia, where it grows along the banks of creeks and rivers. A small perennial herb to about 40cm high, it has a spreading habit and is ideal for moist areas of the garden. It is closely related to another Australian native mint, Mentha satureioides, which has a similar flavour and growth habit. Expect small white flowers in summer and autumn. Native river mint produces 5–6cm-long, intensely flavoured leaves with a beautiful lingering minty aftertaste that’s much sweeter than that of other mints. The smooth, melt-in-the-mouth texture makes it perfect for cocktails.

To keep this plant healthy, water is vital, along with rich, free-draining organic soil (we use a 50:50 mix of premium soil and sand). It prefers semi-shade but will survive in four-to-six hours of full sun. As with Lebanese cress, native river mint will grow happily along the edge of a pond, in a free-draining moist area of the garden or in pots partially submerged in water. If grown in a pot, the vessel needs to be wide enough to allow the mint to spread.

The easiest way to propagate this plant is from cuttings, which root easily in moist free-draining soil from spring to autumn. Unlike common mint, which often dies back in winter, this mint powers year-round with delicious harvests of tiny green leaves.

WATER PARSLEY (Oenanthe javanica)

Otherwise known as Java waterdropwort, water parsley is a perennial semi-aquatic plant widely considered to have originated from East Asia and Australia. Its delicious leaves, with their mild carrot- or parsley-like flavour, make this plant an essential part of our edible garden.

The cultivar ‘Flamingo’ has variegated pale green and white leaves that develop a pink blush when the plant is grown in full sun, making it a striking addition to any garden. The crisp leaves are an excellent source of vitamins and minerals. They can be eaten raw in salads or cooked in soups, pastas and stir-fries. The pink leaves also make a very appetising garnish.

Growing to a height of about 30cm, this small herb has a layering habit that makes it an ideal groundcover for a moist location. It’s also great as a border plant growing at the edge of a pond. It is well-suited as a pot specimen, with the pot partially submerged in water or simply with a saucer of water underneath.

Head to our planting guide for more edible plants to grow and enjoy!

Story by Dr Ketah Silvester
Photo by Shutterstock