Cottonheads

Most Australian gardeners are familiar with the furry flowers of kangaroo paws, but many will not have experienced their hirsute cousins, the cottonheads (Conostylis spp.). There are several dozen species, and they are all tufting, grass-like perennials with spherical clusters of flowers displayed above the foliage. The flowers are usually yellow, but are sometimes white, red or pink. The leaves are often interestingly textured, being felt-like or having fringes of fine hairs on their margins.

Cottonhead varieties

The best-known cottonhead in cultivation is the grey cottonhead (C. candicans), with its tufts of silvery foliage topped by bright yellow balls of flowers. This species is widely grown in Perth, in public and private gardens, where it is often used to create drifts of silver and yellow along sidewalks, and as a border plant in garden beds. The variety ‘Silver Sunrise’ is a more compact form, with bright foliage and flower colour.

There are some unusual and decorative cottonheads that are ideal for pots, such as the variety ‘Bright Sparks’, a selection of C. bealiana, a species from the south coast of Western Australia. The plant’s fine, dark green foliage makes a wonderful contrast to the tubular yellow flowers. Dwarf cottonheads (C. juncea) are similar in form but have interesting wiry leaves. Since both are such small plants, they are particularly effective as a potted plant for a sunny courtyard.

The rather delicate variety ‘Lemon Lights’ – a compact form of C. setigera – produces furry flowers, and the leaves have rows of silvery-white hairs along their edges. This plant looks spectacular when it is backlit, highlighting the beautiful texture of both foliage and flowers. As with all cottonheads, it makes a superb rockery plant, where it blends brilliantly with many other grass-like species, including flax lilies (Dianella spp.) and fine-leafed tufting plants, such as kangaroo grass (Themeda triandra) and common tussock-grass (Poa labillardierei).

Perhaps the toughest of the genus is prickly cottonhead (C. aculeata). It forms a compact clump that is more adaptable to heavier soils than the other varieties, and features masses of yellow flower heads that sit atop the foliage. The plant is aptly named, as the leaves have quite prominent spikes that can be used to advantage in garden design as a spot where small birds, such as wrens and finches, can find shelter from cats and other predators.

Growing cottonheads

Cottonheads are commonly found in the wild as understorey species growing in the eucalypt forests of south-west Western Australia, often in rather sandy, well-drained soils. They flower profusely a year or two after a bushfire, when they are receiving the nutrients from the ash. We can mimic this effect by removing dead flowers and foliage in autumn, followed by feeding them a handful of fertiliser suitable for native plants, and watering it in well.

Conostylis are largely free of pests, however they are quite prone to root and crown rots that can be fatal, particularly when they are grown in poorly drained soils that favour the development of the fungal pathogens responsible for these diseases. Growing them in raised beds, mounds or containers is a great strategy if you do not have well-drained soil. It’s advisable to use a gravel mulch rather than an organic one, to reduce humidity around the crown of the plant.

If you love the look of kangaroo paws, cottonheads make a great companion for them, and both groups create wonderful habitat for wildlife, which is a bonus.

Header image by Angus Stewart