Species distribution and density. Darker squares represent higher density of members of this family.

Introduction

Gladiolus family

A geophytic family of perennial evergreen or deciduous herbs with attractive, colourful flowers, usually with contrasting markings. Well-known as horticulturally important plants, including ornamentals and cut flowers.

The division into subfamilies is based on a series of morphological specialisations. Only four of the subfamilies are represented in southern Africa.

Distribution

Occurring in tropical and temperate regions with an especially high diversity in the winter-rainfall areas of South Africa; also common along the eastern escarpment.

Number of genera in the world

ca. 70

Number of species in the world

ca. 1 800

Number of genera in the Flora of southern Africa region

33

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Number of species in the Flora of southern Africa region

1 204

Well-known southern African genera

Freesia, Gladiolus, Watsonia

Subclasification

1. Subfamily Crocoideae
Mainly deciduous herbs; rootstock a tunicated corm. Inflorescences are spikes (sometimes 1-flowered) of sessile, mostly irregular, variously coloured flowers, lasting at least two days, with a distinct perianth tube and subtended by a pair of bracts; style branches are distinct and slender; floral nectaries are septal.
Well-known FSA genera: Babiana, Chasmanthe, Dierama, Gladiolus, Romulea, Sparaxis, Watsonia.

2. Subfamily Iridoideae
Deciduous or evergreen herbs; rootstock a rhizome or a corm. Rhipidia (umbel-like cymes) not united in pairs, enclosed in opposite spathe-like bracts. Flowers stalked, regular, short-lived, variously coloured, each subtended by a single bract, usually with free tepals; style deeply lobed, with branches often elaborate, petal-like; floral nectaries on tepals.
Well-known FSA genera: Bobartia, Dietes, Ferraria, Moraea.

3. Subfamily Aristeoideae
Evergreen herbs; rootstock a rhizome. Inflorescence consisting of paired rhipidia, enclosed in opposite spathe-like bracts. Flowers stalked, regular, short-lived, mostly blue, each subtended by a single bract, with tepals � free; style notched or lobed; nectaries mostly absent.
Well-known FSA genus: Aristea.

4. Subfamily Nivenioideae
Evergreen shrubs with woody aerial stems; rootstock a woody caudex. Inflorescence consisting of paired rhipidia, enclosed in opposite spathe-like bracts. Flowers sessile, regular, lasting at least two days, each subtended by a single bract, with tepals united in a tube; style notched or with 3 slender branches; floral nectaries are septal.
Well-known FSA genera: Klattia, Nivenia, Witsenia.

Growth forms

Mostly deciduous perennial herbs with rhizomes, corms or rarely bulbs; seldom shrubs.

Habitats

Mostly found in open scrub, grassland and arid vegetation with a few species favouring forest and forest margins.

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Flagship species

Moraea fugax (wituintjie [A]) is a well-known plant from the sandy coastal areas of Namaqualand. The short-lived, white (occasionally also blue or yellow) flowers are pleasantly scented and the corms were (sometimes still are) eaten by the local people. They are either skinned and boiled in milk or roasted in hot ash. According to people who regularly ate these corms, they taste almost like potatoes.

Significance of the family

Very important in the cut flower industry (Freesia, Gladiolus) and as garden subjects (Chasmanthe, Crocosmia, Dietes, Watsonia). Corms of certain members of the family are used as food, especially in Africa. Stigmas of *Crocus sativus are the source of the spice saffron, which is commercially grown in Europe and the Middle East. These stigmas are picked from each flower by hand; 454 g of dry saffron requires 50 000-75 000 flowers, making it the world's most expensive spice. Some Moraea species are poisonous to grazing animals.

Diagnostic characters

Perennials with rhizomes, corms or bulbs. Leaves sword-shaped in 2 ranks (distichous) , usually forming a fan and appearing with the flowers . Inflorescences either clusters of cymes or spikes and usually borne on leafy stems . Flowers mostly regular with the perianth in 2 whorls of 3 tepals each , often united into a tube . Stamens 3, situated opposite the outer tepals . Ovary inferior � with 3 locules. Fruit a loculicidal capsule .

Did you know?

In many genera a long perianth tube is characteristic-an adaptation to pollination by long-tongued flies, birds or moths.