Arum lily
Arum lilies come in two forms. Z. aethiopica from South Africa and its various forms are fully hardy in all but the coldest UK gardens and, even there, if grown properly, they can normally survive and thrive. Z. elliotiana, and its gorgeous, coloured flowering hybrids, are not hardy outside except in the mildest areas. They are therefore best grown in pots and planted out in summer borders before being lifted and re-potted in the greenhouse for the winter.
Both species of arum which we offer are rhizomatous perennials. Z. elliotiana will die down completely in winter while Z. aethiopica will remain evergreen in milder gardens and will not die down at all in a normal winter. When it gets badly frosted it is quite hardy enough to reshoot vigorously from ground level. Arums are best divided in the spring whether dormant or not.
If you are keeping arum in the greenhouse, they require a loam based potting compost in full light. Water freely and feed in the growing season.
Z. aethiopica likes to be grown in full sun and does best with us against a hot wall where it may well not need supports for its tall white flower spathes. With us in Cornwall established plants have leaves which can easily grow to 4ft in height with the flowers well above the leaves. These plants can be grown near water or even in water in a basket planted with soil and lowered into the water. In frosty areas a good winter mulch will help protect the rhizomes and feed them as well. After a mild winter our established plants are normally in flower by April and usually carry on flowering away until the autumn.
Z. aethiopica ‘Crowborough’ is a smaller growing form with a more dense habit and white spathes.
Z. aethiopica ‘Green Goddess’ grows larger in height, but the flower spathes are a dull green with irregular white centres. These also appear right through the growing season.
Z. elliotiana, the golden arum, grows not much more than 2ft in height and, in summer, produces bright yellow spathes above leaves which are white spotted.
Z. elliotiana ‘Black Star’ has maroon-purple flowers and grows to a similar height when mature.
Z. elliotiana ‘Flame’ has red-orange to yellow flowers.
Z. elliotiana ‘Picasso’ has bright clear pink flowers.