Sometimes known as the forest bell bush, Mackaya bella (ht 1.5-2.5m) is a South African member of the broader Acanthaceae plant family, which as includes many plants which thrive in Sydney's climate, such as Justicia, Strobilanthes and Acanthus. It shares with its relatives an ease of cultivation; an ability to grow in shady places; lush and attractive leaves; and decorative two-lipped flowers, with four to five petals (one or more of which may be formed in the shape of a protruding tongue).
Amidst glossy, wavy-edged leaves on a rounded shrub are large, palest lilac-white, bell-like flowers in October and early November, finely etched with purple and each with a flared, three-lobed lower lip, the same shape as those of the oyster plant (Acanthus mollis) without its purple bracts. It thrives in a semi-shaded position and can provide an apt backdrop for its cousin's spires. It is an excellent choice for an informal hedge in a shaded spot. It is sensitive to hard frosts, and needs to be pruned back after flowering for a compact shape. It may self-seed, especially when conditions are damp, so watch out for this.