Category: succulents

Drosanthemum albiflorum

Although the specific name means “with white flowers”, it is not uncommon to come across plants of this species with light to dark pink flowers.
They form erect, much-branched shrublets to 15 cm tall, with leaves that are 7-10 mm long and 4 mm thick, round in cross-section, and with a blunt tip.
Between August and November, the plants produce their flowers at the tips of the branches; they are up to 17 mm in diameter.
In certain parts of the distribution area – stretching from Matjiesfontein to Robertson and Riversdale –  the plants grow in abundance.

Euphorbia grandicornis (Guest column by Theo Heijnsdijk)

Name
Euphorbia grandicornis is a representative of the large group within the genus of shrub-like succulents with spine pairs, also referred to as the diacanthium section. Plants belonging to this group usually have 2 spines that are facing outwards from the edge of a shield. Another example of a member of this group is E. canariensis. Sometimes there are 3 or 4 spines and sometimes only one (for example, in E. unispina).
Grandicornis literally means ‘with large horns’.
In English-speaking countries, the plant is also called ‘Cow’s horn Euphorbia’. The thorns remind me more of the tentacles of a snail. See Fig. 1.

In the next image, we see (between the spines) the scars of the tiny leaves that are formed in the new growth and that will soon turn yellow, shrivel, and fall off.

Other names that are widely used are ‘Big horned Euphorbia’, ‘Rhino thorn’ and even ‘Zig-Zag Cactus’. There is also a cristate form and this looks even much more ferocious than the normal plant. In Afrikaans, the plant is called renosterdoring (a renoster is a rhinoceros and doring stands for thorn).

History
The plant has probably been in cultivation for quite a long time, but for many years it went undescribed.
We first come across the name Euphorbia grandicornis in 1889 in the first part of the 2-volume book ‘Pflanzenbiologische Schilderungen’ by the German professor of botany dr. Karl Immanuel Eberhard Ritter von Goebel. In a general story about Euphorbias, he discusses a number of aspects of E. grandicornis as if it were a well-known plant. It is nothing like what we mean by a description nowadays. However, we do find a beautiful pen drawing of a top cutting (Fig. 3).

In addition, there is a drawing of the leaves in the new growth and of a cross-section of the trunk in which the peculiar, twisted shape of the winged ribs is clearly illustrated (Fig. 4).

Von Goebel reports that he has not been able to find any data on the habitat. However, from the physical appearance of the plant with the wide thin ribs and therefore a large surface area – similar to, for example, leaf cacti- he concludes that it is unlikely to be exposed to long dry periods in its natural environment.
After von Goebel it was quiet until 1893. In that year, an article by a Mr. J.E. Weiss, Reader in botany, appeared in the periodical ‘Dr. Neubert’s Deutsches Garten-Magazin’ under the title “Empfehlenswerte Cacteen” (“recommendable cacti”). He took the concept of cactus rather broadly because the last ‘cactus’ discussed in his article is Euphorbia grandicornis. There is even a photo, the very first one published, but the print quality was rather poor in those days (Fig. 5).

Original description
The plant was still not officially described at the time. That was done in 1897 by Nicholas Edward Brown in part 26 of Hooker’s Icones Plantarum. That is why the author’s citation which is always added to the species name in scientific literature, in this case is ‘Goebel ex N.E. Br.’. The description by Brown, who was employed by Kew Gardens near London, was based on a plant that had been cultivated there since 1876. The description with Latin diagnosis was accompanied by two drawings of quite a big specimen. I don’t particularly like these drawings. Brown also mentioned a locality: South Africa, Umfolosi River, Zululand.

Habitat
Nevertheless, there was apparently uncertainty as to where the plant occurred in nature, because in 1904 in Engler’s ‘Botanische Jahrbücher’ ( ‘Botanical Yearbooks’) in a monography on Euphorbia’s in the section Diacanthium the author, F. Pax, writes: “Vaterland unbekannt, vielleicht Africa”  (Native country unknown, maybe Africa). And in 1907 Alwin Berger in his ‘Sukkulente Euphorbien’ says: “Homeland ?”  and further down:
The origin of the plant is unknown. However, it is not plausible that it was only recently introduced, because the large specimen in Kew mentioned above, indicates that it is an old inhabitant of our greenhouses.). Brown and others later compiled the part about the Euphorbiaceae in Sir William T Thiselthon-Dyer’s ‘Flora Capensis’. This part appeared in 1915 and here E. grandicornis is also treated.  The last line I find quite funny: “Distribution: Easter Region: Zululand, stone! Marriott! And cultivated specimens!”.
I suspect Marriott is a name, but I haven’t been able to find any information. But especially all those exclamation marks intrigue me. I have no idea what the writer wanted to emphasize with this.
In modern literature, it is made clear that the range is quite large: South Africa (Kwazulu-Natal), Swaziland, Mozambique, Kenya. There the plants grow at low altitudes (up to 400 m) in small groups between grass or shrubs. They have 3 or 4 ribs and can be up to 2 m tall. It seems that large plants often succumb to their own weight. The variety sejuncta (described in 1970 by Leach), which remains smaller and sometimes grows lying down, has 2 or 3 ribs and is known only from a site in Mozambique. There it grows in the company of Aloe chabaudii, Euphorbia corniculata and E. tirucalli on granite slopes at altitudes between 380 and 700 meters.

Flowering
In a sunny location, a plant that is preparing to flower stands out because of the vivid red colour of the developing cyathia (Fig. 6).

These appear on the uppermost and therefore youngest, segments of the stems. There are always 3 cyathia together, but often only the middle one will fully develop. It only produces male flowers (stamens). The two outer cyathia are bisexual. First, the male flowers develop (Fig. 7)

and when they dry out, the female flower (pistil, fig. 8) follows.

All cyathia are bright yellow in colour. This type of inflorescence with a central male inflorescence flanked by 2 bisexual cyathia is often found in Euphorbias, for example in E. canariensis.
Ripe fruits are about 8 mm in diameter and purplish-red in colour (Fig. 9).

Fruit formation in a E. grandicornis in Jan Celliers Park (Pretoria, South Africa).  Photo Dr. Johann C. Knobel.

Cultivation
A well-drained mixture with little organic material and a lot of additions such as lava, pumice, clay chunks, etc. is recommended. It’s best not to use peat. Give ample water from March to September. In winter, the temperature should be at least 12 °C, but preferably a little higher. Propagation is by cuttings, which root quite easily, or by sowing. Seed is fairly well available and it is fascinating to see how a wildly thorned plant develops from the delicate seedling with its 2 cotyledons (Fig. 10).

In frost-free areas, E. grandicornis is recommended for hedges. Pruning is well tolerated. Goats eat the corners off but leave the thorny sides alone. The juice doesn’t seem to hurt them.

Literature:
Berger, A. (1907). Sukkulente Euphorbien: 52-53.
Brown, N.E. (1897). Hooker’s Icones Plantarum 26, plates 2531, 2532.
Brown, N.E.; Hutchinson, J.; Prain, D. (1915). Euphorbiaceae in Thiselton-Dyer, Flora Capensis 5, sect 2, part 2: 367-368.
Goebel, K. von (1889). ‘Pflanzenbiologische Schilderungen’ 1: 62-63.
Pax, F. (1905).. Monographische Übersicht über die afrikanische Arten aus der Sektion Diacanthium der Gattung Euphorbia in Engler’s Botanische Jahrbücher 34: 74.
Weiss, J.E. (1893). Dr. Neubert’s Deutsches Garten-Magazin 46: 291.

First published in Succulenta 92 (4) 2013. Translation from the Dutch by F.N.

 

Didierea madagascariensis (sogno)

Of the two species of Didierea (the other one is D. trollii), this is by far the most widespread and best-known. It occurs abundantly on red sandy soils in SW Madagascar, from the dry spiny bush in the Toliara area northwards to the Morondava river.
D. madagascariensis has quite a distinctive growth form: the single trunk is up to 0.5 m thick and 6 m or more tall;  it is generally unbranched up to 2 m high.
The branches usually grow more or less upright and are often curved towards the top; the short lateral shoots give rise to clusters of very long spines (up to 12 cm) and groups of short-lived, greyish green and narrow leaves (7-15 cm long and 0.3-1 cm  wide).
The inflorescences may cover extensive areas of the upper branches. The numerous unisexual flowers are pale yellowish to greenish-red and open only during sunny weather between 10 am and 2 pm to be pollinated by bees.
In cultivation, the plants are often propagated by grafting a short-shoot on a strong plant of Alluaudia procera, thereby producing nice specimens within 3 to 4 years.

 

 

 

 

 

Crassula multicava

Crassula multicava

(Guest column by Theo Heijnsdijk)

Crassula multicava (Fig. 1) is a sparsely branched plant with fleshy stems  up to about 30 cm long and 1 cm thick. Long stems lie down and form new roots and branches from the leaf axils. The leathery leaves are up to 6,5 cm long and 4 cm wide. Towards the stem, each leaf narrows down to a petiole (leaf stalk), which is fused with that of the opposite leaf, giving the impression that the stem has grown through them.
C. multicava occurs in South Africa (Mpumalanga, KwaZulu-Natal, Eastern Cape) and was described by Lemaire as early as 1872. Multicava means: with many cavities. This refers to the upper side of the leaf, which is littered with many round dimples, somewhat like an orange (see Fig. 2 below),


Fig. 2
(giving rise to the name ‘Pitted Crassula’. The dimples are so-called hydathodes, a name for glands that can excrete moisture. Such glands occur in many plant genera and can be of different anatomical origins. In Crassulas, they are converted stomata. As a rule, hydathodes are intended to get rid of excess moisture, but that sounds rather strange for succulents, who need to lose as little moisture as possible. Gordon Rowley in his book ‘Crassula’ suggests the possibility that during the day when temperatures are very high, air bubbles are formed in the vascular system of the plant so that the juice flow is blocked (embolism), comparable to air bubbles in a garden hose. At night, the plant would then supply extra water from the roots, thereby increasing the pressure so that the air dissolves back into the plant juice. Then the excess water must evaporate again via the hydathodes. Rowley invites readers to come up with a better theory.

In a shady place, the leaves are fairly light green (Fig.3 above).
In a sunny position, they stay smaller and are much darker green with the leaf edges and hydathodes turning brownish-red. By the way, in dappled shade, they also grow better than in full sun. In Afrikaans, the plant is not called ‘skaduplakkie’ (shadow crassula) without reason.

My first introduction to the species was during the Christmas holidays of 2005, when I stayed on the Canary Island of Gomera. I went for a walk near the apartment and came across a garden in which the soil was covered with a layer of perennial succulents with lots of pink flowers. By the way, the plant had not kept to the boundaries of the garden. Of course, there was no name sign. In May 2008, I saw the plant for a second time (now properly labeled), as a ground cover in a bed with other succulents in a greenhouse of the Botanical Garden of Berlin.

In my greenhouse (in the Netherlands) the plant blooms abundantly from March /April until well into autumn. The flowers are rather loosely arranged in the inflorescence, which results in a somewhat unkempt look. (Fig. 4 below).


Fig. 4
It reminds one of a cloud of mosquitoes and I think that is why the plant is sometimes called the ‘Mosquito Flower’ in America.
Crassula flowers perfectly conform to the prototype of a flower as you find in, for example, a biology book for schools. From the outside going to the centre, one first comes across the calyx leaves, then, alternating in position relative to these, the same number of petals, then alternating again, the same number of stamens and lastly, in alternating position again, the same number of pistils on top of the ovary. Such a flower structure with all this in equal numbers is called isomerous. With most Crassulas, the flowers are 5-merous, so 5 of all the above parts, but in C. multicava the flowers are usually 4-merous. They are white inside and pink on the outside  (Fig. 5).


Fig. 5
The appearance of the star-shaped pink flower is the reason that the plant is called ‘feetjie plakkie’ or ‘feetjie crassula’ in Afrikaans. A feetjie is a fairy in English, so there it becomes fairy crassula. In Australia, the plant is called ‘London Pride’, because the plant in flower resembles Saxifraga ‘London Pride’, used as a ground cover in England. By the way, ‘London Pride’ is also the name for a multi-award-winning English beer variety.
Due to the large number of flowers, the flowering stems bend to the ground. By the time the flowering season ends, miniature versions of the plant (called bulbils, see Fig. 6 and 7 below) appear here and there on the flower stalks.


Fig. 6


Fig. 7
This is quite normal for some Kalanchoes (Bryophyllums), but exceptional in the genus Crassula. These plantlets easily become detached from the mother plant and then quickly take root. This way, in a suitable climate such as in the Canary Islands, the plant can become a pest. The name ‘Cape Province Pygmy weed’ also refers to the rampant character. I don’t know what it has to do with pygmies, but maybe it only refers to the small size of each plant.
The regenerative capacity of C. multicava is phenomenal. As early as 1938, a scientific paper was published describing how new plants can emerge from epidermis cells of small cut-off pieces of leaf. In these times of tissue culture, this may not sound so spectacular, but at the time it was considered a unique trait.
Rowley attributes the great regenerative capacity and the forming of bulbils to the large number of chromosomes of C. multicava. As we know, almost all hereditary information of an organism is recorded on the chromosomes, which are located in the nucleus of each cell. In general, in a nucleus there are 2 sets of chromosomes, 1 set originated from the father and 1 set from the mother. This is called diploid and the number of chromosomes is then indicated as 2n. The number of chromosomes  in a set is indicated by the letter x. Normally,  x  =  n. For a fruit fly x = 4 applies, for a human x = 23, for a guinea pig x = 32  and for most Crassulas  x  = 7. A human being has 2n = 2x = 46 chromosomes. In some species there are more than 2 sets and such a cell is called polyploid. In plant species that are normally diploid, polyploidy often leads to larger individuals or larger flowers. In Crassula, no less than 44% of the species are polyploid. The champion is C. spathulata with 2n = 20x = 140,  which indicates 20 sets of 7  chromosomes per cell nucleus. C. multicava comes second with 2n = 16x = 112, so 16 sets.
I must admit that the link between a high number of chromosomes and a high reproductive capacity is not clear to me. Of other polyploid Crassulas it is not recorded that they reproduce so easily and neither do they do form bulbils, whereas C. cordata, which does make bulbils, is just diploid. Maybe someone should come up with a better theory here, too.

As for cultivation: frost-free, although they seem to be able to endure a single bit of frost without damage. Otherwise indestructible. The plant also grows well in shade.

There is a subspecies,  C. multicava subsp. floribunda. This one is a bit more robust in all parts and the flowers are 5-merous. It has a cultivar, C. multicava subsp. floribunda ‘Panache’, in which the edges of the leaves are whitish-yellow. C. multicava subsp. multicava, on the other hand, has a forma ‘Variegata’  in which the leaves are green at the edges but yellow in the centre.

Literature:
Harders, C.L. (1932). Crassulaceae, Succulenta 15 (11): 207.
Rowley, G. (2003).  Crassula, Cactus & Co.
McVeigh, I (1938). Regeneration in Crassula multicava, American Journal of Botany 25: 7 -11.

First published in Succulenta 90, (1) 2011. Translated from Dutch by FN.

Cephalophyllum purpureo-album

Because of the epithet purpureo-album (purple-white), one would expect most -if not all- plants of the species to have purple flowers with white stamens. That may have been the case in the plant on which the original description was based, but yellow flowers with pale yellow (or white) stamens are much more common.

The plants form clumps up to 60 cm in diameter with more or less cylindrical, mostly dark green leaves, which are about 6-10 cm long and more slender than in other Cephalophyllums.
In May-September, they produce yellow or pale purple flowers up to 5 cm in diameter with 70-110 petals and up to 260 stamens. The number of compartments in the fruits is also high (13-17).

Judging from the number of synonyms (C. aurantiacum, C. gracile, C. littlewoodii, C. middlemostii, C. paucifolium, C. serratulum and C. worcesterense), the species is quite variable.
It occurs in the western Little Karoo and in the Robertson Karoo, where the plants are often locally abundant in open patches on sandy, loamy or gravelly flats.
In a suitable (Mediterranean-like) climate, the species – just as many other Cephalophyllums- will make an excellent garden plant.

 

Kumara plicatilis (Guest column by Theo Heijnsdijk)

History
Kumara plicatilis, better known as Aloe plicatilis, has been in cultivation for a very long time. It is certain that around 1690, the plant was grown in the famous garden of the United East-India Company (VOC) in Cape Town (now called the Company’s Garden). It was more than 60 years before 1753 when Linnaeus introduced the binary nomenclature in his ‘Species Plantarum’ in which species were recorded by means of a genus name followed by the species name. Until then, people used a short description in Latin. In this case:
Aloe Africana arborescens Montana non Spinosa, folio longissimo plicatili, Flore rubro.
In English, this roughly means: “an African aloe developing into a tree, growing in the mountains, without spines, with very long folded leaves and red flowers”.
Obviously, referring to a plant or animal in this way becomes overly complex as more and more species are discovered.

The Latin description was given by Heinrich Bernhard Oldenland, a.k.a. Henrik Bernard Oldenland (in botanical literature: Henricus Bernardus Oldenlandus). He was born in Germany in or around 1663, studied medicine and botany in Leiden, and had arrived in Cape Town in 1688 as an employee of the VOC. It is quite possible that in 1689 he himself brought along K. plicatilis as a participant in a 3-month expedition that went all the way to present-day Aberdeen. From 1693 until his early death in 1697, he was the head of the company garden.

The oldest known image of K. plicatilis is a water colour painting made in 1694 by Alida Withoos (fig. 1). This painting and 12 other water colours were commissioned by Joan Huydecoper, who between 1673 and 1693 was mayor of Amsterdam no less than 13 times, and Jan Commelin  (Joanne Commelino), a merchant in herbs and medicinal drugs, whose last name is also spelled Commelijn. In 1682, these two gentlemen had initiated the creation of a Hortus Medicus (a garden with medicinal plants) in Amsterdam. Such a garden already existed at the Binnengasthuis, but as garden lovers, they wanted to make the scope a bit wider and also offer space for ornamental plants. So, in fact, they established a botanical garden (the forerunner of the current Hortus Botanicus). Thanks to their many contacts (Huydecoper was a member of the board of the VOC and a cousin of Simon van der Stel, the governor of the Cape of Good Hope), they were able to obtain plant material from many parts of the world.

The Moninckx atlas
Huydecoper and Commelin did not create a herbarium, but instead, they set up a kind of image bank. They called it “Figures of foreign plants, in the Medicinal Garden of the city of Amsteldam”. The image bank consists of 420 water colours on sheets of parchment paper about 56 by 40 cm in size. These paintings were produced between 1686 and 1707. By far most of them (273) were made by Jan Moninckx. In addition, 101 were made by Maria Moninckx (it is unknown which family relationship these two had). Then of course  Alida Withoos with 13 works and finally Johanna Helena Herolt-Graff with 2 drawings. The remaining 31 water colours are not signed. Alida Withoos also painted Tulista (Haworthia) minima as part of the same assignment, a duo – water colour of Haw. retusa with Tulista (Haw.) margaritifera and also Aloe vera. For the latter she used two sheets of parchment: one was for the plant with the lower part of the flower stem and on the other sheet the flower stem continued to end in a beautiful, branched bunch of yellow flowers. The parchment sheets were later pasted on paper and bound. All this resulted in eight tomes. The complete series is called the Moninckx atlas. The tomes were published between 1686 and 1709. All 420 plates can be seen on the website of the University of Amsterdam. In 1749 a ninth part was started but eventually contained only five paintings.

Jan Commelin had also begun to depict and describe the plants in the Hortus Medicus in a series of books, but he died in1692. The first volume, called “Rariorum Plantarum Horti Medici Amstelodamensis descriptio & icones” appeared posthumously in 1697. After this, the work was continued by his nephew and successor Casper, a.k.a. Casparo Commelino. In 1701, part 2 was published. In this section, the South African plants, including Kumara plicatilis are discussed. One of the nice things about these books is that everything, including the title sheet, is written in both Latin and Dutch. See figure 2 for the Dutch title sheet.
In describing K. plicatilis, he writes “This plant grows at the Cape of Good Hope on high mountains in the rocks thirteen feet high, and one and a half feet thick and bears flowers in the month of October“. He also mentions, among other things, that the older leaves are not stiff as in most Aloes, but slightly folded. This explains the name plicatilis (= folded). In drawing 3, the leaves are also clearly shown this way. He goes on to write that the plant has been growing in the Hortus Medicus for many years, but without flowering and that the flowers and the fruit have been re-drawn from a book by Nicolaas Witsen “who has lent me this book showing all kinds of plants in Africa painted from life”. Nicholas Witsen was also mayor of Amsterdam (between 1682 and 1706) and administrator of the VOC and friends with Simon van der Stel and his son and successor Willem Adriaen. He also was an enthusiastic collector of fossils, minerals, archaeological finds, animals, plants, and drawings of all that. The drawings of South African plants and animals were collected in three tomes called the ‘Codex Witsenii’. Of these, only Part 1 has been preserved. K. plicatilis is not mentioned in there.

Nomenclature
Linnaeus described the species in 1753 as a variety of Aloe disticha (distichus = in two rows). In 1768, Philip Miller elevated the variety to species. Those who search well can also find the plant under the name Aloe linguaeformis (1782, Linnaeus the younger), Aloe tripetala (1783, Friedrich Medikus), Aloe lingua (1785, Thunberg), Kumara disticha (Friedrich Medikus,1786), A. flabelliformis (Salisbury,1796), Rhipidodendrum plicatile (Haworth, 1821) and also under some even less well-known names. Lingua, by the way, means tongue and linguaeformis is tongue-shaped, obviously referring to the shape of the leaf.
The name Aloe, by the way, is many centuries old. It is assumed to come from the Arabic ‘alloh’ (or ‘alloch’ or ‘alloeh’), which is the name for bitter substances such as the juice of aloes.
The fan-shaped growth, K. plicatilis has in common with K. haemanthifolia, which occurs in the same area. Until recently, both were classified in the subgenus ‘Kumara’. Partly on the basis of DNA research, this subgenus was recently (2013) elevated to genus level.
In South Africa, an Aloe is often called an Aalwyn. Because of its shape, K. plicatilis is called the ‘Fanaalwyn’. The name ‘Bergaalwyn’ is also used in connection with the occurrence in the mountains. The leaf shape gives rise to the name ‘Tongaalwyn’. The name ‘Franschoekaalwyn’ (after the habitat) is also used. while the resemblance to Aloidendron (Aloe) dichotomum (the quiver tree) has earned it the name ‘Cape Quiver Tree’.

Nature
The species occurs in the mountains of the Western Cape, from Elandskloof to Franschhoek. This is an area with a Mediterranean climate and rainfall mainly in winter. The annual rainfall is between 600 and 1500 mm.
The plants grow on steep, rocky slopes facing south (please remember, that in the southern hemisphere this is the side with the least sun) in well-drained, sandy, slightly acidic soil. See images 4 – 6. They can become up to 5 meters tall. In nature, only the tops of the stems bear leaves. These are strap-shaped, up to 30 cm long, and 4 cm wide. Salm-Dyck also described a var. major in which the leaves grow to more than 30 cm long and 5 cm wide, but to me that does not sound like a substantial difference.

It seems that there are about seventeen separate localities, all of which are at least 10 km apart. Although the species is quite rare, it is not threatened. There are several protected areas in which the plants occur, such as the Jonkershoek Nature Reserve, the Hottentots Holland Nature Reserve, the Limit Mountain Nature Reserve, and Horse Mountain Nature Reserve.
In nature, plants are sometimes damaged by the Cape klipdas (Procavia capensis capensis), which in South Africa is called ‘dassie’.
In periods of drought, these animals, which look a bit like guinea pigs, climb to the top of the branches, where they first gnaw away the bark and then feast on the juicy inner parts.  They continue to do that until the branch collapses. If the fallen branch does not end up on bare rock, but on soil, it will root quite quickly. A kind of unintentional propagation.

The habitats are characterized by the typically South African fynbos vegetation (Mediterranean-like), with among other things Protea and Erica species. As Commelin reported, the plants bloom in October, at the end of winter.

As is the case with A. vera, the sap has healing properties associated with injuries and is sometimes drunk to stimulate the immune system. There are also reports that the juice is used as a remedy against diabetes.

Cultivation
K. plicatilis is easy to grow. Due to the fact that the conditions in cultivation are usually less harsh, the leaves are preserved for much longer, allowing the plants to bear leaves from bottom to top. See the photo of a specimen in Madeira’s botanical garden (fig. 7 and 8).

In accordance with the natural growing conditions, a well-drained soil with a pH  between 5.5 and 6.5 is recommended. In the Northern hemisphere, growth is in summer. In winter, the plant should be kept dry. In summer, they can also be kept outside. Propagation can be done by seed or cuttings. At 20°C, the seeds germinate after about 4 weeks. The species is known as a slow grower. Yet they can also reach a considerable size in cultivation, even in a greenhouse.

In 1904, Alwin Berger reported a crossing with Gonialoe (Aloe) variegata, the partridge Aloe. The hybrid was allegedly produced by the Englishman Justus Corderoy and was therefore called Aloe x Corderoyi. Maybe he expected the result of the cross between these totally different aloes to be something spectacular, but in fact, it was disappointing. The plants are very similar to  K. plicatilis. Only the leaves are arranged in a spiral around the trunk, in contrast to K. plicatilis, in which they are in two straight rows.

Literature:
Berger, A. (1904): A new Aloe hybrid, Monatschrift fuer Kakteenkunde 14:61
Commelin, C. (1701). Rariorum Plantarum Horti Medici Amstelodamensis Historia: 5
Engler, H.G.A. (1908). Das Pflanzenreich, regni vegetabilis conspectus, 38: 322 – 324
Website about the plants of South Africa: http://www.plantzafrica.com/plantab/aloeplicatilis.htm
The Moninckx Atlas can be found via the URL: https://allardpierson.nl/collecties/natuurlijke-historie/moninckx-atlas/moninckx-atlas-index/#l


Fig. 1. Water colour of Kumara plicatilis made by Alida Withoos for the Moninckx atlas in 1694.


Fig. 2. Title page of “Rariorum Plantarum Horti Medici Amstelodamensis Historia” (part 2) by Casper Commelin published in 1701.


Fig. 3. Drawing of Kumara plicatilis in “Rariorum Plantarum Horti Medici Amstelodamensis Historia” (part 2) by Casper Commelin published in 1701.


Fig. 4. A large Kumara plicatilis in the Du Toits gorge in the Western Cape
(photo Coby Keizer).


Fig. 5. In nature, only the tops of the branches of Kumara plicatilis bear leaves  (photo Wim Alsemgeest).


Fig. 6. In the new growth, the tips of the leaves are tinged red
(photo Bertus Spee).


Fig. 7. Kumara plicatilis in the Botanical Garden of Madeira in full swing with flowers and fruits.


Fig. 8. Kumara plicatilis in bloom in the Botanical Garden of Madeira.

 

 

 

Aloidendron (Aloe) eminens

Common names: Somali tree aloe, Daar Der (= the tall Aloe)

Of the seven Aloidendron species, only two are found outside Namibia, South Africa, and Mozambique:  A. sabaeum (Arabian peninsula) and A. eminens, which at first glance is somewhat similar to the much more familiar A. barberae from South Africa.
It is an upright tree 10-15 m tall, looking somewhat untidy because of its irregularly branching. Its trunk is up to 1.5 m in diameter at ground level.
16-20 leaves are gathered at the tip of each branch; they are 40-45 cm long and about 5 cm wide at the base, gradually narrowing to an obtuse, downwards pointing tip. The upper surface is dull-green and u-shaped in cross-section, whereas the lower surface is rounded; the margins are white with blunt teeth.
The branched inflorescences are 50-60 cm high, with red, somewhat glossy flowers, which are cylindrical-trigonous on cross-section, rather thick and fleshy, and about 4 cm long. They appear mostly in November-February and are pollinated by birds.

Although the species is still locally common in northern Somaliland, it is endangered by habitat loss, logging, and wood harvesting.
It occurs in sheltered, well-wooded ravines and on steep rocky limestone slopes North of Erigavo (Ceerigabo), between about 1500 and 2000 m. The climate is relatively cool here with between 600-1000mm rain per year.

 

 

Ceropegia stapeliiformis (*Guest column by Theo Heijnsdijk)

Introduction by Frans Noltee
Some ten years ago, the Dutch journal Succulenta featured the first of what was to become a long series of articles on well-known cacti and other succulents in cultivation, written by Theo Heijnsdijk. Recently the author approached me to ask if I might be able to supply him with a habitat photo for an article in this series. That request caused me to have a new look at the articles he had published and this, in turn, convinced me that some of them would fit into my blog and indeed make a worthy addition to it.
When I suggested this to Theo, he was very enthusiastic about it and as a result, I am now grateful and proud to publish the first of what will hopefully become a series of articles on African succulents in cultivation.

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Ceropegia stapeliiformis was sent to Europe in 1826 and described in 1827 by the English botanist Adrian Haworth. The name of the plant (often wrongly spelled as stapeliaeformis), obviously refers to the resemblance of the non-flowering stems to those of a Stapelia.
When not in flower, C. stapeliiformis is not particularly attractive. The stems are about as thick as a finger and crawling, climbing, or winding; usually, they are leafless with rudiments of leaf stalks. They are greyish brown (to olive green in cultivation), often with stripes or dots.
But the blooms make up for it. When C. stapeliiformis is preparing to flower, it will form tendrils, i.e. long thin stems (up to 1.5 m),  which like to wind themselves around a stick or something similar (see picture 1).


Fig. 1: Winding flowering shoot of C. stapeliiformis

In nature, these flowering stems swing up in bushes, probably to make the flowers easier to find and more accessible to pollinators (small flies).
Several flowers develop in succession on a flower stem (peduncle); they form a hairless tube at the bottom which becomes funnel-shaped higher up and ends in five narrow outward-curved petals. These petals are hairless on the outside and covered with white hairs on the inside. Their colour varies from reddish-brown (picture 2) to green with white (picture 3). The total length of a flower is about 6 cm.

picture 2


picture 3

The oldest image I could find was in Curtis’s Botanical Magazine of 1837, plate 3567. A particularly beautiful image can be found in year 2 of the horticultural magazine ‘Flore des serres et des jardins de l’Europe’ (see picture 4).

picture 4

This magazine was published between 1845 and 1883 and consisted of 23 volumes with more than 2000 coloured plates. It was founded by the Belgian horticulturalist and botanist Louis Benoit van Houtte (1810-1876). From 1836 to 1838 he was director of the National Botanic Garden of Belgium in Brussels. Later he started a nursery/ floristry. Around 1870 the nursery occupied 14 hectares and there were no less than 50 greenhouses. From 1845 he sent collectors to Central and South America. They brought back rare plants such as orchids. He was also the first on the European mainland to have the giant water lily (Victoria amazonica) in cultivation and to get it into bloom.

C. stapeliiformis occurs in the Eastern Cape, south of the 31st parallel, where it usually grows in the shelter of scrub.
C. serpentina (described in 1949) nowadays is considered a subspecies of C. stapeliiformis.
So, we have C. stapeliiformis subsp. stapeliiformis (the original species) and C. stapeliiformis subsp. serpentina (= like a snake). The latter occurs north of the 29th parallel, in the north-east of South Africa, and in Eswatini (the former Swaziland).

Many publications mention the curious tendency of the stems to suddenly grow down, drill into the ground and reappear at some distance.  Let’s have a look at what Chr. de Ringh wrote in the Dutch magazine ‘Succulenta’ in December 1933:

Gradually, an offshoot developed at the bottom of the cutting. It lifted itself above the ground for a while and then drilled its tip into the soil. I let it do its thing and within a short time, it had gone deep down. One day it reappeared above ground some 20 cm away and then quickly grew to a big affair of about a metre long. Such a stem prefers to turn around a stick and then go up like a bean around a stake. Although my patience had been tested for a long time, I was finally rewarded as well as surprised when buds appeared.

The flowering period in cultivation is from April to October (in nature October to March) and a large plant may produce hundreds of flowers in this time.
As far as cultivation is concerned: use well-drained soil (with e.g. 1/3 coarse sand and an addition of clay); in summer ample and in winter little or no water. Beware of stagnant moisture, because that will cause the plant to rot quickly. Rotting also occurs if temperatures are too low and/or humidity too high in winter. Temperatures should not be below 5 to 8° C.

Propagation is possible by cuttings or seed. Sowing is fun and not difficult. The seeds are flat and fairly large and germinate within a few days. In the third year, seedlings may already flower.
Unfortunately, we rarely find the species in the seed lists. This must have something to do with the complicated pollination mechanism of the family to which the Ceropegias belong. For those interested (and able to read Dutch), I can recommend the description by Arie de Graaf in ‘Succulenta’ of February 1977. After a successful pollination, the bipartite fruit develops. It resembles two pods that grow in a V-shape on a common stalk. The length of a pod is about 10 cm. When it matures, such a  pod tears open  (picture 5) and then unrolls.


Fig. 5 Opening fruit

The seeds are now ready to be on their way. Like the seeds of a Senecio (or of a dandelion and such), they are equipped with a tuft of white hairs (picture 6).

Fig. 6. Open fruit with seeds

This way they can be taken by the wind and land at some distance from the mother plant. The tuft of hairs will disappear somewhat later. The seeds germinate after a few days and the plantlets will grow fast (picture 7).


Fig. 7. A group of one-year-old seedlings in a 5.5 cm pot

Usually, we will have to use cuttings for propagation. The best time for this is spring. Because the cuttings often bleed, it is advisable to dip the cut surface in charcoal, ash, or something like that first. Of course, one should allow the cuttings to dry first (about ten days), before sticking them into the ground. It will take about a month before roots appear.

Literature:
Haworth, A. (1827). Description of new succulent plants, The philosophical magazine or annals of chemistry, mathematics, astronomy, natural history and general science: 121.
Lemaire, C. (1846). Flore des serres et des jardins de l’Europe 2 (6): t4.
Noltee, F and H. van Donkelaar (1965). Ceropegia stapeliaeformis, Succulenta 44 (5): 70-72.
Ringh, Chr. De (1933). Ceropegia stapeliiformis, Succulenta 15 (12): 217-219.
Sims, J. (1837).  Ceropegia stapeliiformis, Curtis’s Botanical Magazine 64: t 3567.
Soldt Sr., O. van (1977). Het lelijke eendje dat een wondermooie zwaan werd. Succulenta 56(2): 47-50.

Originally published in Succulenta 89 (3) 2010. Translated from Dutch by FN.
Author’s email:  th.heijnsdijk@gmail.com

Fig. 1: Winding flowering shoot of C. stapeliiformis


Fig. 2: A flowering C. stapeliiformis lives up to the name lantern plant


Fig. 3. C. stapeliiformis flower with green petals

Fig. 4. Coloured plate of C. stapeliiformis in Flore des serres et des jardins de l’Europe (1846)


Fig. 5 Opening fruit


Fig. 6. Open fruit with seeds

Fig. 7. A group of one-year-old seedlings in a 5.5 cm pot

 

 

Aloe humilis (Hedgehog Aloe, Krimpvarkieaalwyn)

Although this species is very variable, it is easy to recognize (Aloe longistyla is somewhat similar, but usually grows as a single plant). The distribution area stretches from Mossel Bay to Graaff-Reinet and Somerset West, and the plants are most abundant in rocky loamy soils under shrubs. Plants from the Eastern Cape (pics 5 -7) are less robust than those from the southwestern part of the area (pics 1 – 4).

“Humilis” means “low growing” and refers to the stemless rosettes, which usually form dense clumps up to 40 cm or more in diameter. Each rosette consists of 20-30 leaves, erect or slightly incurved, with a distinct grey-green waxy layer, unspotted, about 10 cm long and up to 1.8 cm broad, with many small soft white prickles on both surfaces and soft white teeth along the margins.
About 20 flowers are gathered in single inflorescences of up to 35 cm tall. They appear from August to October and are scarlet or more rarely orange or yellow. With a length of about 4 cm, they are rather large for such a small plant.

It may be of interest to note that the species was cultivated in the Dutch East India Company’s garden in Cape Town as early as 1695.

Braunsia (Lampranthus) maximilianii

If I were to make a list of my favourite succulents, this species would have quite a high ranking on it. I’m not completely sure why that is: because of the beautifully shaped and coloured leaves, because of the delicate way the plants hug the ground, because of the size of the flowers compared to the rest of the plant or maybe a combination of all this. Their natural habitat is in shallow pans on rocks pavements, often together with moss, in the northernmost part of the Cape Province from the Bokkeveld Mts. to Piketberg. This area receives about 125 mm rainfall per year, mainly in winter.

The plants are mat-forming with creeping stems to 17 cm long, which form roots at the nodes.
They have boat-shaped, pale grey-green, velvety leaves with dark keel and margins and fused for more than half their length, 6-10 mm long, 5-6 mm wide and 6-8 mm thick.
The flowers are quite large (to 2.5 cm in diameter) and bright pink; they appear between July and October.

Common names: bloukraalvygie, kruipvygie

Note : the name of the species is spelt here with ‘ii’ because ‘Maximilian’ is not considered to be a latinized name, and therefore ‘maximiliani’ has to be corrected by adding an ‘i’ (ICBN Art. 60.11).