Gymnocalycium continued

Gymnocalycium mihanovichii has already been referred lo under G.damsii. Il forms small clumps by producing offsets at the sides of the plant from the areoles, and it is a low-growing variety normally only attaining a height of 3 in (8 cm). The stems are olive green in colour and the true species is characterized by paler bands running between the areoles. The ribs, which are normally eight in number, are broad and deeply notched with areoles about half an inch (Icm) apart and live or six radial spines but no centrals. The flowers are a greenish-yellow colour and the true species has a faint red coloration near the edge of the petals.

Gymnocalycium m.friedrichii is altogether a much smaller plant and the plant bodies are curious in that they lack almost completely any trace of green colouring, being instead suffused with a brownish-purple coloration. The ribs are more sharply angled than those of the true species and the lateral banding of paler colours is more prominent. The spines are very much scarcer than those of the species and this is due to a large extent to the lack of chlorophyll. The flowers, which are seldom produced on cultivated specimens, are pink in colour and similar to those of G. lafaldense.

Hibotan varieties of G. mihanovichii are those in which the production of the green chlorophyll pigmentation has been stopped almost completely. It is not uncommon for both G. mihanovichii and G. tftwlt/uinum to produce variegated patches on one of their ribs. If the central growing area of the plant is then removed carefully with an apple corer the growing point may be induced to form an offset which will have the same coloration. Once the offset is formed it must be grafted on lo another species as it lacks the means of supporting itself by photosynthesis.

Il is possible to buy plants of this variety which have already been grafted and the production of different coloured forms has become something of a cult in Japan. Four distinct colour varieties are available - red, by far the most common and the most satisfactory. pink, yellow and white. The red ones will produce rudimentary flowers and although these will reach the normal size as buds they are unlikely to open properly into full flower. As the plants mature further offsets will be produced from the areoles of coloured plants and these may be grafted on to fresh stocks in their turn. The coloration frequently disappears near the growing point where it becomes green, this can be reduced lo some extent by giving the plant a brighter position but some green pigmentation must occur if the plant is to grow at all.

Gymnocalycium mulliflorum. in spite of flowerers of the genus. The spines are arranged like spiders' legs in two parallel rows on either side of the areoles and are normally between six and ten in number. The areoles are more or less distant from one another and carried on Ihe broad ribs, which number up to fifteen on mature specimens and surround the plant bodies. It is possible thai some hybridization has occurred with other less free-flowering varie ties of Gymnocalycium and this may account for the variable ease with which cultivated specimens may be flowered, although once the plant has attained a diameter of- about 3 in (8 cm) it seems that il may be flowered fairly freely.

Gymnocalycium ourselianum is somewhat similar in appearance but has fewer spines, seldom more lhan seven in number, and Ihe flowers are ralher fuller giving it the appearance of being semi-double. There may. however, be some confusion between G. mulliflorum and G. ourselianum.

deserves a plate in every collection, par-

flower during the season and the flowers arc produced right through the summer into the late autumn. The plant bodies are a bluish grey in colour and very much flattened, seldom exceeding 2Jin (6-5 cm) in height. They are surrounded by ten low ribs which are prominently divided up into the chins or tubercles so typical of this group of plants. The spines, which are normally only five in number, are flattened back against the plant bodies and are produced from more or less well-spaced areoles which carry a little wool alongside the

Although a reliable flowerer it is subject to curious attacks of brown discoloration in the winter and particular care must be taken not to allow the plant to shrivel through overwintering in too warm an environment. I can offer no cure for these brown patches, which appear on the plant unpredictably and frequently with little ill-effect. It is possible that they are the symptoms of a virus or bacterial infection which is harmless as long as it is not allowed to gel out of hand; but a certain amount of bronzing on the plants, particularly if the plants are grown in good light during the summer, is quite normal. The brown discoloration normally only manifests itself during the late autumn.

Gymnocalycium plalense has plant bodies of similar colour and appearance when young but develops a much less squashed and more globular habit with age. The flowers of both species are white but those of G. quehliamun have a magnificent deep red throat and are produced on longer tubes. Once again it is probable that hybridization has occurred here amongst commercially produced plants as there is a great deal of variation in G. quehlianum in

Gymnocalycium saglione is a species best grown for its attractive spines rather than for any hope of flowers. It is a native of North-western Argentina and very slow growing. It is occasionally grafted and this makes a very much larger, more robust plant, which ultimately attains a size of nearly a foot (30 cm) in diameter. The tubercles in this species have become so prominent that it is difficult to distinguish it from a mammillaria and the ribs are not at all clear, particularly as the areoles are very large and occupy nearly all the outer surface of the tubercle. When young the spines have a magnificent, almost black, coloration but as they mature this turns to red and subsequently fades to a greyish colour nearer the base of the stem. The colour of the spines can reputedly be maintained by overhead watering, but if this is tried it should be done early in the morning so that no puddles remain in the growing tip which might act as magnifying glasses for the sun's rays and scorch the plant's growing point. As mentioned earlier, the pink flowers are only produced on older specimens and the plants are even more difficult than most gymnocalyciums to raise

Gymnocalycium venturianian and G.bal-

diamun are probably the same species and are distinguished from all other gymnocalyciums by the magnificent red flowers which are freely produced even on younger specimens. The ribs are at first fairly prominent with a conspicuous edge but this becomes flatter with age. The habit is at first hemispherical and the plant body looks slightly squashed but ultimately it develops a more globular shape. The spines are few and curved, grey at the tip becoming darker near the base, and the plant bodies are a greyish blue-green in colour. The areoles are divided from one another by deep V-shaped notches and the lower part of the tubercle has the characteristic chin-like appearance of other members of the genus.

Flowery Cactus Illustrated





The three varieties illustrated on this page are so diverse in form that it is difficult to believe that they are all basically of the same subtribe. let alone of the same family. Hamatocactus setispinus unlike the other two is a fairly common species and makes an excellent addition to the collection producing flowers through from midsummer until the drying-out period is begun in late autumn. The plant bodies are generally dark green and spherical although in the autumn as drying out commences they can become much paler and may even be suffused with a reddish-purple tinge, particularly on the side which gets the most sunshine. There are generally thirteen deeply divided ribs which can even be somewhat wavy in a manner reminiscent of Ecliinofossulocacti. The areoles are closely spaced, about half an inch (1 cm) or so apart, and are borne on pronounced pimples or tuberclcs on the edges of the ribs which consequently appear to be sharply notched between them. The radials are somewhat variable in number, generally twelve, at first reddish but becoming pale white or straw coloured with age and during the winter, the colour persisting longest in the upper three. The centrals are somewhat variable on cultivated specimens. Flowers are very freely produced even on quite young plants and arc a magnificent yellow in colour often 2 in (Scm) or so in diameter and in many horticultural specimens have a red throat.

There is another species called H. hama-tacanthus which has larger spines, the central one being flattened on the upper 138 surface and the areoles being borne on much more pronounced tubercles.

Leuclitenbergia principis is a great rarity whose tubercles have become so prominent as to dominate the entire planl giving it the appearance of the grass on the pampas amongst which it grows. It is rather rare on account of its very slow growth and the difficulty with which it is kept alive during the English winter when it has a distinct tendency to suffer from fungal attacks. For this reason young plants are frequently grafted on to somewhat hardier stock and then re-established on their own roots when they are of a fair size.

The tubercles themselves are bluish green and arc prominently three sided with thin papery spines produced at the tips. It is quite normal for the older tubercles to dry up and fall off giving the plant the appearance of having a short trunk. The flowers are very spectacular, pale yellow, produced amongst the upper spines, but only on well established specimens normally of nine years of age or more. During the summer it should be stood in the brightest position possible, on a shelf in the greenhouse if this is available, and during the winter it needs only quite normal temperatures. It seems to do well in a rather more open compost than that used for most cacti and I recommend adding more peal for this purpose.

Mescalin is distilled from the planl bodies of Lophophora williamsii to which the Yaqui Indians ascribe almost divine powers. Its rounded spineless plant bodies taper into a thick tap root and it benefits from the addition of some crushed brick to the compost to ensure adequate drainage at all times. A curious feature of the plant is the way in which the hairs in the areoles are tufted up into small points. The areoles are in turn produced on tubercles which are so flattened as to be barely recognizable as such. The drug is obtained from the dried body of the plant which is sliced and dried

In spite of its poisonous nature and its rarity it makes a good plant for the average collection since it flowers quite readily and the buttons or offsets can be grafted on to rather stronger stock in order to multiply it up. Buttons are normally produced in the fourth or fifth year and seem to do better when grafted than when grown on their own roots. The flowers, which arc produced in the woolly top of the plant, are small and throughout the summer.

Continue reading here: Malacocarpus

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