The species of this genus which we offer originate from New Zealand and are perennials with short rhizomatous roots. Burncoose has been importing these plants from New Zealand for many years and we have become increasingly convinced of their hardiness in all but the very coldest parts of the country. Astelia form bold clumps of arching leaves covered in silvery white scales. As such they make very attractive foliage plants in a variety of different situations. They complement other ornamental grasses evergreen or otherwise, they do not get as large or out of control as Cortaderia and they make good central feature plants in a colourful herbaceous border. Their winter colour is as useful as that of Phormium or New Zealand flax and these are often grown together. Although one thinks of Astelia as plants which grow best in full sun Ventnor Botanic Garden has a fine display of Astelia with evergreen ferns beside a shady ravine.
A. chathamica ‘Silver Shadow’ and ‘Silver Spear’ are two of the most popular and vigorous clump forming varieties. The individual silvery leaves can be 3-4ft long in maturity and clumps will grow to 4ft in height with a greater width as offsets from the main clump develop. The panicles of pale greenish-yellow flowers are borne in April or May and are followed by orange berries but it is the leaf form which is the main attraction.
A. nervosa ‘Red Devil’ and ‘Westland’ are smaller growing and will achieve about 2ft in height in maturity. The foliage is silvery-bronze turning redder in colder conditions. The flowers are greenish-yellow or brownish-purple in summer and are followed by orange or red berries.
A. banksii is also slower growing and a smaller clump forming species than A. chathamica. Its leaves are silver-green and narrower. A clump may achieve 3ft in height eventually.
A. fragrans has sword like green leaves and green flowers.
Astelia do best in moist fertile soil and can readily be propagated from seed sown as soon as they are ripe in containers. Offsets can be lifted and divided from clumps over winter to create new plants.