Senna coronilloides (Cassia coronilloides)
What a pity it is that in a country as richly endowed as Australia is with Cassias and Sennas, we are more familiar with the foreign cassias that have been brought into the country by the nursery industry. Some of them have gone on to become serious environmental weeds. What a waste, when our own beautiful, easy to grow, hardy native cassias are hardly used in gardens at all.
This one is an example.
It is common in the scrubs on the Darling Downs, and is a very attractive shoulder-high shrub with a long flowering season. It grows happily on a variety of soil types, is hardy to drought and (mild) frosts, and likes full sun or part shade.
The plant on the right is garden-grown, and one year old.
Like all the cassias (native and introduced) it is not long-lived, but good care and annual pruning can prolong its life.
New plants are easily grown from seed.
The plant's common name comes from its richly brown, ripe seedpods, which open along one side like a hinged jewellery box, and display neatly arranged, shiny, black seeds on a soft tan background. Half of them adhere to one side of the pod, while the others (every second seed) are displayed on the other side. If you get the sun on them at the right angle they gleam an iridescent green.
Cassias are outstandingly good butterfly-attracting plants, used by half-a dozen or more of our local species of yellow butterflies which breed on them, and come to the flowers for nectar.