This is a shrubby member from Peru of the Acanthaceae family of plants, which contains many excellent specimens for Sydney gardens. It grows to 1-2 m in height and has attractively veined, lance-shaped leaves. The inflorescences comprise upright spikes of golden-yellow bracts holding white flowers - giving rise to its common name of 'golden candles'. It blooms for an extended period during the warmer months and continues into autumn. It will grow in semi-shade or sun and appreciates a reasonable soil and occasional watering. It should be pruned hard at the end of winter, otherwise it will become straggly. It is easily grown from cuttings. Pachystachys does not like very frosty winters. In very cold suburbs, it can be kept going by taking cuttings in autumn and keeping these protected during winter.
It looks effective grown with foliage plants that have some yellow variegations - such as Canna 'Striata', Euonymus japonicus 'Aureus', or Miscanthus sinensis 'Zebrinus' - or as part of a hot-coloured planting scheme with orange and red flowers, such as Dahlia and Salvia. There is a red Pachystachys (P. coccinea) but I have yet to see it in a Sydney garden.