Arum Lily, Calla Lily, Pig lily, Kleinvarkoor, Witvarkoor, mohalalitoe, magapule, intebe, ihlukwe, ilabatheka-elimhlophe, ilabatheka-omhlophe (Zantedeschia)
Today a new generation of Zantedeschia hybrids have been bred from our original indigenous species; not only for their spectacular fashionable colours but for their sheer flower power. These new varieties produce many more blooms from a given tuber size, and the number of flowers produced by a tuber is directly proportional to the size of the tuber of each specific variety. Each year after the tuber has produced its magic, it will grow bigger in size, to produce more and even taller blooms the following season. These popular varieties are grown in the garden and in pots not only for the wonderful show they put on, but also for the production of magnificent cut flowers for the vase. Zantedeschia hybrids are easy to grow, and provide gardeners with a vast array of rainbow colours to enjoy in all shades of pink, yellow, white, cream, apricot, peach, orange, purple(almost black) and red.
Zantedeschias are members of the very large plant family Araceae which includes the well-known delicious monster (Monstera deliciosa); the Flamingo flower (Anthurium andraeanum); as well as the black calla lily (Arum palaestinum) from the Middle East. Arum lilies are wonderful clump-forming perennials which are grown worldwide for their lush foliage and ornate blooms. Most species are deciduous but some may remain evergreen; surviving the dry season by storing water in their fleshy rhizomes (modified underground stems of a plant). Interestingly, the colourful part of the plant which we refer to as the flower is actually a large modified leaf wrapped around a central finger-like stem called the spadix, which carries the minute but densely congested flowers. The coloured spathes can be funnel-shaped or cylindrical; and come in white, yellow, pink or red, with or without a dark purple marking at the base inside. The flowers are followed by green berries which ripen to orange.
The genus is restricted to the African continent with eight species recognised; seven of which occur only in South Africa, concentrated mainly in the summer rainfall regions: Zantedeschia aethiopica, Z. albomaculata, Z. elliottiana, Z. jucunda, Z. odoratum, Z. pentlandii and Z. rehmannii. The centre of diversity for the genus is around Lydenburg in Mpumalanga where four species occur: Zantedeschia albomaculata extends into south-central Africa and northwards to Tanzania; Zantedeschia aethiopica is widespread and commonly found in marshy areas; Zantedeschia elliotiana is known only in cultivation; and Zantedeschia odorata is restricted to Nieuwoudtville in the Northern Cape. Sadly Zantedeschia jucunda and Zantedeschia pentlandii are under severe threat partly because of their beautiful colourful spathes which are dug up by locals when in full bloom for the horticultural trade. Subpopulations of Zantedeschia pentlandii are fragmented and are also declining due to mining. Zantedeschia odorata and Zantedeschia valida seem to be less threatened by locals because of their white spathes, but need to be conserved because of their restricted distribution range.
In the wild plants of Zantedeschia occur in areas with seasonal rainfall; growing in the grassland, savanna and fynbos biomes in full sun, less often in semi-shade. Most species commonly grow between rocks with their tubers buried in the crevices to keep them cool and to protect them from porcupines. It is believed that beetles are the main pollinators because beetles belonging to the family (Scarabaeidae) are known to mate inside the spathes, with the female laying her eggs at the base.
Pictures of all the following varieties can be seen at www.plantzafrica.com
(Zantedeschia aethiopica) The common or white arum is widespread and can be found growing wild from the Western Cape through the Eastern Cape, KwaZulu-Natal; Mpumalanga and into the Northern Province. It is evergreen or deciduous depending on habitat and rainfall; in the Western Cape it is dormant in summer and in the summer rainfall areas it is dormant in winter. It will remain evergreen in both regions if growing in marshy conditions which remain wet all year around. It has lush dark green leaves with an arrow-head shape and grows vigorously to + 60cm to 1m tall. This arum will grow in full sun or semi-shade but will get taller in the shade. The large pure white spathes can appear anytime of the year but their main flush is from August to January. They are most adaptable, forming large colonies in marshy areas from the coast to an altitude of 2 250m. Because they tolerate humidity, salt laden winds at the coast, and freezing, misty mountain grasslands at high altitudes, they make extremely versatile garden plants and are the most commonly planted arum lily. Nowadays there are other forms of this species like ‘Marshmallow’ with its creamy-pink spathes and rose-pink throat; ‘Green Goddess’ with its enormous leaves and unusual green and white spathes; and ‘Spotted Leaf’ with its attractive large spotted leaves and creamy spathes.
(Zantedeschia albomaculata) is deciduous and grows in small clumps, up to 70cm tall; with oblong to arrow-shaped leaves, often speckled with white spots. The spathes are cylindrical and a white, cream or pale yellow; often marked with dark purple at the base.
(Zantedeschia subsp. Albomaculata) is a subspecies with oblong leaves and which flowers from October to April. It grows wild in the Eastern Cape, KwaZulu-Natal, Lesotho, Free State, Swaziland, Mpumalanga and Limpopo; extending into Zimbabwe, Malawi, Zambia, Angola and Tanzania. It is commonly found growing along rocky hillsides, forest margins and stream banks.
(Zantedeschia subsp. Macrocarpa) is a subspecies with triangular leaves; flowering from November to April with a peak in December. It occurs in KwaZulu-Natal, Lesotho, Free State, Swaziland, Mpumalanga and Gauteng; growing in grassy vleis and on marshy ground beside streams.
(Zantedeschia rehmannii) The pink arums are small to medium plants 20 to 60cm tall, with lance-shaped, dark green leaves which are very rarely speckled with white spots. The cylindrical spathes appear from September to February, with a peak in November to January; in colours ranging from white through shades of pink to dark maroon (almost black). This arum occurs from Harrismith in the Free State and northern KwaZulu-Natal, through Swaziland to Mpumalanga and is commonly found growing in semi-shade amongst rocks on grassy hillsides; at medium and quite high altitudes; at forest margins and in sandy furrows.
(Zantedeschia elliotiana) is probably a hybrid of garden origin because specimens have not been found in the wild; and its suspected parents include Z. pentlandii or Z. jucunda; and Z. albomaculata subsp. albomaculata. This deciduous species grows +-60cm tall and produces large, very attractive, broadly ovate deep-green leaves, speckled with white spots. Flowers are produced in abundance from November to January; and the cup-shaped spathes are bright golden-yellow with a purple base.
(Zantedeschia odorata) is a deciduous species which grows +-70cm tall and produces beautiful large broadly ovate dark green leaves. The spathes are white and appear from July to August. It is restricted to an area known as Klip Koppies at Nieuwoudtville in the Northern Cape; occurring on outcrops formed by large dolerite boulders which break down to form a red clay soil which retains water well in the rainy season; so the roots are in seasonally very wet soil and occasionally in standing water.
(Zantedeschia jucunda) is a deciduous species which grows +-80cm tall with arrowhead shaped leaves, with triangular lobes branching out from the base of the leaf approximately at right angles. Flowering is from November to January and the spathe is a cup-shaped funnel which can be a deep or creamy yellow with a dark purple base. It is confined to the grassy slopes of the summit of the Leolo Mountains in the Sekhukuneland Centre of Floristic Endemism, where it grows in full sun. Sekhukhuneland is a small area in north-eastern South Africa in the provinces of Limpopo and Mpumalanga which has rich biodiversity and a high level of endemism (species unique to a defined geographic location).
(Zantedeschia pentlandii) The yellow arum is a deciduous species which grows +-60cm tall with broadly ovate, blue-green leaves which are very rarely speckled with white spots. Flowering is from November to December, and the attractive funnel-shaped spathes are a brilliant chrome yellow with dark purple bases. This species is restricted to the Mapoch region of Mpumalanga, comprising the northern part of the Belfast District and adjoining parts of the Lydenburg District, where the plants often grow in dense colonies wedged between rocks.
(Zantedeschia valida) is a deciduous species which is quite vigorous and grows +-75cm tall with broadly ovate green leaves. It flowers from October to March, peaking in November. The creamy yellow spathe is a cup-shaped funnel with a dark purple base. This species is restricted to the region bordered by the Biggarsberg, Giants Castle and Collin’s Pass in KwaZulu-Natal; where it grows wild amongst rocks on the mountains, in clefts and on foothills; as well as on the banks of streams and in vleis.
In the pioneer days tubers of the common or white arum (Z. aethiopica) were boiled and fed to pigs, hence their common name ‘pig lily’ or ‘varkoor’. The common or white arum (Zantedeschia aethiopica) is used by traditional healers and the warmed leaves are applied as a poultice to treat sores, boils, insect bites, gout and rheumatism. A decoction of (Z. albomaculata) is used by Zulu women to prevent repeated miscarriages and giving birth to weak babies.
Because Zantedeschia contains calcium oxalate, and ingestion of the raw plant may cause a severe burning sensation and swelling of lips, tongue, and throat; stomach pain and diarrhoea is also possible; it is not advisable to allow pets, horses or cattle to graze these plants.
The leaves of the common or white arum (Z. aethiopica) are cooked as a pot herb by South Africans; especially in the African and Indian communities. The Africans boil the leaves before braising them in oil with onions and chillies, and serving with maize meal porridge. Indians braise the leaves with onions and chillies before adding tamarind water and boiling until tender. Tamarind seems to effectively break down raphides of calcium oxalate in the leaves; but if the plant is not properly cooked it will cause a burning sensation in the mouth and throat.
Although eating raw tubers causes irritation of the mouth, the tubers of Z. aethiopica and Z. albomaculata are sometimes cooked and eaten by communities in southern Africa; but though they are a good source of starch, the tubers are not commonly used as a food crop.
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In the Garden:
The remarkable Zantedeschia is sure to impress any visitor to your garden; and today a new generation of hybrids have been bred from our original indigenous species; not only for their spectacular fashionable colours but also for their sheer flower power and rainbow of colours. These new arums need at least 6 hours sun a day and are lovely planted in containers or in the garden. When your planter is a mass of colour, bring it onto the patio, place it beside the pool or on the deck and enjoy the sheer magic in your summer entertainment area.
The white or common arum (Zantedeschia aethiopica) can be planted in ordinary garden beds, but is ideal as a marginal plant alongside streams, or on the edge of a pond; and can even be planted into a pot and submerged into water, as it does not need drainage. It makes a useful foliage plant in shade under trees but in deep shade will not flower very well. All arum lilies make excellent cut flowers and the ripe fruits are relished by birds.
Arums grow best in moist, temperate climates, but grow easily throughout most of the country as long as they can be watered regularly. Because the plants are generally dormant during the cold winter months they are reasonably hardy, but some species are hardier than others; and the colourful new hybrids are not fully hardy; so in very cold gardens protect the overwintering crowns by covering with straw, newspaper or even cardboard anchored with pegged down chicken wire. Ensure they are not overwatered – the cooler the temperature, the less water will be required. If your arums receive watering along with the rest of your garden they may not go totally dormant and the foliage will be blackened by the first frost, this should be cut away.
Alternatively, you can lift the tubers and store them until early spring when the risk of frost has passed. Store them in trays of compost, vermiculite or wood chips; in a cool, dark, frost-free place such as a garage or shed. Potted plants can be overwintered at a minimum temperature of 10°C indoors or in a warm greenhouse or conservatory.
The hardy forms of zantedeschia are Zantedeschia aethiopica and Z. pentlandii and their cultivars. The tender forms of zantedeschia are mainly cultivars of Z. elliotiana and Z. rehmannii (also called Elliottiana hybrids and Rehmannii hybrids), but may also include Z. albomaculata and Z. jucunda. Zantedeschia aethiopica and its cultivars are also tender.
Except for the common or white arum which grows in full sun or semi-shade; they all thrive in full sun (at least 6 hours a day). The common white arum (Z. aethiopica) will also grow well in deep shade, but the plants will grow taller and won’t flower very well. Although most species are have a period of dormancy, the plants may remain evergreen if they are watered throughout the year, or are grown in marshy conditions. In marshy soil they can spread vigorously, forming large colonies of plants. It is important to remember that they like rich soil containing generous amounts of well-decomposed plant matter; and respond well to regular applications of compost, kraal manure or organic fertiliser.
The various species vary in height from 60cm to 1m tall, with the flower stems reaching even taller. Spring is the main planting season and the tubers are planted roughly 15cm apart and 5cm under the soil’s surface. Tubers of the new hybrids will always remain true to their colour; but any fallen seed which germinates will result in a variety of indistinct colours; so to keep the colour true you need to remove all spent blooms to prevent the setting of seed. To harvest flowers for the vase run your fingers to the base of the flower stem and pull it out (do not cut with a knife as the remaining stem could initiate tuber rot).
To plant into pots; choose a large planter, preferably made from terracotta and plant groups of single or mixed colours, spaced about 15 cm apart. Dwarf varieties like Pot Black, Pink Pot, Jack of Hearts and Cracker Jack are perfect in pots. Use a top quality branded potting medium that drains very well and place crocks over the drainage holes to keep them open; this is very important. Plant the tubers in exactly the same way as you would do in the garden and keep in the full sun. When the show is over and the foliage turns yellow and dies down, your container will start to look unsightly, so move it to the back yard or another location where the natural maturation process will continue normally to produce an even more spectacular show the following season. Cover the bare soil with a thick layer of mulch or even layered newspaper to save the soil from freezing in the winter frost; and keep the soil damp but not wet.
Once you have planted your bulbs they can be left undisturbed in the ground for many years. Every spring simply give them a top dressing of manure or compost, and this together with regular, deep watering is all they will need to stimulate flowering again.
Zantedeschia plants propagate well from seed and by splitting the tubers in early spring. Large overwintered clumps in the garden can be divided in the same way as other perennials, by lifting the plant before there is much top growth, and chopping through the roots with a spade and dividing into smaller sections. Small rhizomes that have been overwintered in pots under cover can literally be cut up into sections, each with a visible bud and the pieces re-planted about 5cm deep. If the plant is not dormant, it can still be propagated by division by using a sharp spade to cut out a section for replanting.
The fruits can be harvested in summer when they are ripe and have turned yellowish and soft; remove the pulp and allow the seeds to dry before storing for sowing in spring. Sow into trays or pots using a well-draining seedling mix and covering the seed lightly. Take care not to sow too thickly as the new plants will need space to form their fleshy roots. Maintain a temperature of 20°C and germination should take place after only a couple of weeks, but the little plants will take 2 to 3 years to flower.
Pests & Diseases:
Zantedeschia is relatively disease and pest free if grown correctly but watch out for slugs and snails. Caterpillars and especially hawk moth caterpillars sometimes feed on the young leaves of at the start of the growing season, making plants appear leafless. They may also suffer from aphid, red spider mite or whitefly damage if grown in a very sheltered environment or under cover in a glasshouse or conservatory. Species with colourful spathes are more susceptible to soft rot, caused by the Erwinia bacterium. Conditions for soft rot are favourable when temperatures and humidity are high or nitrogen levels in the soil are high and aeration low.
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Zantedeschia contains calcium oxalate, and ingestion of the raw plant may cause a severe burning sensation and swelling of lips, tongue, and throat; stomach pain and diarrhoea is also possible.
The information contained within this website is for educational purposes only, recording the traditional uses of specific plants as recorded through history.