There are more than 200 species of Oxalis in South Africa and 270 varieties and probably many new species as well. The only handbook on the Southern African species, by Salter, is almost sixty years old and out of print so there are many challenges in identifying them. Cape Plants, a conspectus of the Cape flora of South Africa by Peter Goldblatt and John Manning lists 118 in the Cape Floral Kingdom but there is only a brief botanical description, location sometimes with habitat information, and time of bloom in this book.
South African species C are found on this wiki page.
South African Oxalis A-B – South African Oxalis D-E – South African Oxalis F-G – South African Oxalis H-K – South African Oxalis L-M – South African Oxalis N-O – South African Oxalis P – South African Oxalis R-S – South African Oxalis T-Z – South American Oxalis – Miscellaneous Oxalis – Oxalis index
Oxalis callosa has trifoliolate leaves and rose-red flowers with a purple ring and a yellow tube. It is an especially beautiful South African species found on gravely soils from the Bokkeveld Mountains to the western Karoo. It blooms in the fall. Photos by Mary Sue Ittner and Bob Rutemoeller.
Oxalis caprina described as a weed by some, grows from the southwest Cape to the Eastern Cape. It has trifoliolate leaves and 2 to 4 flowers lilac to white flowers per stem. It has a long bloom period. Photos by Mary Sue Ittner.
Oxalis clavifolia is a low growing rambling plant when grown by me, but according to the literature it should be erect when growing in its native south and western Namaqualand. The flower is a brilliant yellow and with a purple margin on the underside. The stems are covered with viscous hairs, and the leaves club-shaped, giving rise to the latin name. Photos by Christiaan van Schalkwyk.
Oxalis commutata MV5117, a plant collected by Michael Vassar at Vanrhynshoek, has lavendar flowers held above the tiny leaves. It blooms in the fall. Michael thought it to be this species. Oxalis commutata increases rapidly so might need to be watched for weed status. Photo by Mary Sue Ittner.
Oxalis comosa is common in Namaqualand, from Kamieskroon in the south, extending beyond Concordia in the North. The first photograph is of one from the Nababeep area (south of Springbok). It is one of the only few shade loving species, and if it grows among or in bushes can reach up to a metre in hight. Plants in sunny spots are much smaller and densely branched. The bulb is long and spindle shaped; the bulb tunics are light brown and smooth. Plants grown under this name are most often not this species, but rather the large flowered form of Oxalis obtusa, which can be distinguished by its totally different growth habit and bulbs. The first photo by Christiaan van Schalkwyk. The next two were taken by Bob Rutemoeller and Mary Sue Ittner in Namaqualand September 2006.
Oxalis compressa is found in the Northwest to Southwest Cape and has more than one flower in the peduncle (2-6), trifoliate leaves and compressed leaf stalks and is often confused with Oxalis pes-caprae. The first photo is of a plant collected by Johannes-Ulrich Urban outside Vanrhynsdorp in hard gravel. It forms a rosette of bright green leaves with reddish-brown stems and many bright yellow flowers blooming above the leaves in winter. This plant, Oxalis sp. Uli63 , is most likely Oxalis compressa. The second photo shows the unusual bulbs on a 1 cm. square grid. Photos by Mary Sue Ittner.
For more information regarding this species and its look-alikes, see O. copiosa
Oxalis convexula is a winter spring bloomer with rosy-salmon flowers with a yellow throat. Leaflets are in threes, thick and fleshy. The flowers need warmth to open. The pictures below by Mary Sue Ittner December 2003 and January 2004 are taken on different days illustrating the leaves and open buds and on a second day the buds open even more. The third picture was taken after I brought it inside where it was warmer so the flowers would open. The fourth picture is of a plant four years after its last transplant. The original single bulb managed to form about 80 bulbs in these four years. In the last picture a part of this clump and some single bulbs can be seen on a 1 cm. grid. The thick fleshy stems seen in the first and fourth photos are characteristic of this species. The last two pictures were taken by Christiaan van Schalkwyk.
Oxalis copiosa is a yellow flowering species often confused with other similar species, namely O. pes-caprae, O. compressa and O. haedulipes. All four have umbels of yellow flowers, although O. copiosa has only 1 to 2 flowers per stalk, often only one flower in the beginning of the season, later progressing to two. If there is only one flower, one can still see the upper articulation of the flower stalk set at the bracts.
O. compressa can be identified by the flattened or compressed leaf stalks.
O. pes-caprae has a brown bulb, without conspicuous longitudinal grooves. It may or may not have a stem. The bulbs of O. copiosa and O. haedulipes are similar: greyish and with conspicuous longitudinal grooves. O. copiosa never has a stem, while O. haedulipes always has an exserted stem.
Here is Oxalis copiosa from southern Namaqualand. Photos by Christiaan van Schalkwyk.
South African Oxalis A-B – South African Oxalis D-E – South African Oxalis F-G – South African Oxalis H-K – South African Oxalis L-M – South African Oxalis N-O – South African Oxalis P – South African Oxalis R-S – South African Oxalis T-Z – South American Oxalis – Miscellaneous Oxalis – Oxalis index