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Many wildflowers are bursting at the seams this month, but there are some that are hardly ever considered in the home garden yet are deserving of a place in the native section of gardening.
Commonly known as coneflowers, isopogons and petrophile have striking foliage and unusual flowers. Most are small shrubs that attract all the nectar feeding birds and in the South West, honey possums.
Isopogon and petrophile are closely related and often mistaken as being the same plant. Both have flowers in heads or short terminal, or axillary spikes attached to the stem. The flowers are either cream, yellow, or pink from late winter through to summer.
It is a shame so few species of petrophile are cultivated for sale in nurseries as they have interesting flowers and foliage, look great in a vase and of course are incredibly drought and heat resistant. On the other hand, a few species of isopogon are readily available from native specialists and have been cultivated for the cut flower industry for many years.
Isopogons are commonly called the rose coneflower because of the shape of the flower. They are in the same family as banksias, grevilleas, and hakeas. There are some that specialist native nurseries supply, the most common being isopogon formosus. It is a small shrub growing to only 1.5-2m high with rose-pink flowers clustered together to form a flower head at the ends of branches. The fruiting cone is held on the plant giving it an architectural look.
Isopogon dubious also has pink flowers but remarkably interesting foliage, with wavy leaves divided into three spoon shaped leaves. It is a small shrub growing to only 70cm high and wide.
Isopogon latifolius has striking foliage with broad crinkled spear shaped leaves and pink pom pom heads.
Many petrophiles have yellow flowers, except petrophile axillaris with pink flowers. P. squamata is the most striking with yellow fluffy flowers and leaves that are divided into three to nine lobes, which makes great foliage for the vase.
All the smaller birds love these plants as they are prickly and provide protection from predators as well as being nectar rich. It’s worth chasing them up from either Zanthorrea Nursery in Maida Vale or Australian Native Nursery in Oakford.
Always lightly prune after flowering finishes to promote denser growth and encourage more flowering. Isopogons and petrophiles must be fertilised with low phosphorus fertiliser and the best time is in late winter.