Justicia adhatoda is one of the tallest of this genus and can reach heights of up to 4 m. One of the earliest discovered members of the Acanthaceae family, it was first found in India and was treated as a greenhouse plant in England. It has large attractive shiny leaves that have a limy tinge in their new growth, which associate well with lime-coloured flowers out at the same time, such as those of Nicotiana langsdorffii. The flowers - appearing in late winter and spring - are held in spikes and they have the typical two-lipped form, similar to those of Acanthus mollis, and they are white with a purple netting on the lower lip.
It grows best in shaded or semi-shaded areas, and it will tolerate dry soil. It forms a good background screen to lower plantings and has a nice domed shape. It is known to be susceptible to phytophthora root rot - which can cause it to drop dead overnight. So far, this hasn't happened in my garden. Incorporation of lots of organic matter into the soil when planting may help this problem. Its leaves are claimed to have medicinal uses. It should be pruned back hard after flowering and given some general purpose fertiliser at this time. Cuttings taken in spring or early autumn should strike easily.
Flowers in August, September, October.