There are a few perennial wallflower cultivars that do quite well in Sydney, flowering in late winter and through spring. I am not sure of their parentage. One example is 'Apricot Twist', which grows to around 60cm. It has clusters of delightful orange blooms which associate well with other hot-coloured plants flowering at this time. It also looks effective grown with Mediterranean plants out at this time such as rosemary, Euphorbia and perennial statice.
Another pretty cultivar has bright yellow flowers; sadly I don't know its name. Like most wallflowers, these cultivars like a sunny, dryish position and a little lime added to the soil. They should be trimmed back after flowering. I find wallflowers are not long lived in our Sydney climate, but it is fairly easy to propagate them from cuttings.
These plants are attractive to bees.