There are six species of Sparaxis in South Africa, and three of them are naturalised in Western Australia. The plants in Western Australia are of garden origin, and many of them may be hybrids and not easily attributable to species. They all spread from corms and seeds. S. bulbifera is the most common species, a serious invader of clay wetlands on the Swan Coastal Plain and Avon Valley. It has large, cream flowers in spring. S. grandiflora has either purple or yellow flowers and hybridises with S. bulbifera. It is found around the Metropolitan area and old settlements in the wheatbelt.
Sparaxis
bulbifera
, RR
S. pillansii (harlequin flower) is the most striking of the three. Its petals are tricoloured, usually red, then yellow, with a black centre, but the outer portion can be pink or purple. It is found around old settlements from Perth to Albany.
S. pillansii , SE
There are 28 species of Tritonia in South Africa, and two of them are naturalised in Western Australia. All increase readily from seed and corms. T. crocata has brilliant orange flowers,
Tritonia
crocata
, PH
and T. lineata has cream flowers with dark veining on the outside of the petals. They both flower in spring and are found around old settlements and on roadsides between Perth, Bunbury and Albany.
T. lineata , PH
Southern Africa has about 70 species of Watsonia (all species PP), and so far six, all garden escapes, have been recorded as naturalised in Western Australia. All arise from corms, and form clumps of stiff, sword-shaped, upright leaves. Most spread by seeds and corms. Since they are of garden origin, it is often difficult to place them into exact species. W. bulbillifera (bulbil watsonia) has dull orange flowers in late spring.
Watsonia
bulbillifera , RR
It is considered by some authors to be merely a horticultural form of W. meriana, but it is easily distinguished when in fruit, as it forms many small corms at each node up the flowering stalk, and these spread it very efficiently along rivers, wetlands and roadside table drains. It is a very serious weed in the wetter south-west and south coast.
W.bulbillifera , PH
W. marginata has open, pale lilac flowers. It occurs around old settlements from the Darling Range near Perth to Albany.
W.
marginata
, PH
W. meriana typically has dull orange flowers, but it may also be white, pink, or cerise. It is very similar to bulbil watsonia, but apart from not producing bulbils, it also tends to grow in sites where the soil dries out in summer, for example, around granite rocks, and in wandoo woodlands. A serious environmental weed, it is found between Perth and Albany.
W.
meriana
, PH
W. versfeldii is a tall, showy plant, with white, pink, cerise or red flowers. It is a serious weed of roadsides and granite rocks between Perth and Albany.
W.
versfeldii
, GK
Hybrids of W. borbonica can be found around Perth. They have open flowers in a variety of pinks and white.
W. borbonica hybrid, GK
