The "True" Christmas Cactus
Schlumbergera x buckleyi

Schlumbergera truncata was originally named Cactus truncatus. It later joined Epiphyllum with E. Russellianum. Both, along with their hybrids, were subsequently transferred to Zygocactus, and then to Schlumbergera.

The Florist and Pomologist 1: 13-15 (Jan 1868)
Epiphyllum truncatum and its varieties
William Buckley
Garden Companion and Florists' Guide p. 45 (Jan to Oct 1852)
3. Epiphyllum Buckleyi 2. E. Rollissonii
(both from Russellianum x Truncatum)
THE Epiphyllum truncatum has always, since its first introduction from Brazil in 1818, received the attention of cultivators, and many a hoary-headed son of Adam has pointed with pride to the big Cactus at the end of the vinery, now all a-blaze with blossom, that had been grafted by himself some twenty years before. At intervals a few others were obtained, as E. truncatum bicolor, Bridgesii, and rubro-tinctum; and in 1839 the lovely E. Russellianum made its appearance, also from Brazil. This latter, although recorded as a variety of E. truncatum, is certainly a distinct species, for while the varieties of E. truncatum usually flower in November and December, the natural blooming period for E. Russellianum is the month of May. There are, besides, other differences, the petals being evenly reflexed, the stamens straight, and the seed-vessel angular; while in E. truncatum the flower is ringent, the stamens curved, and the seed-vessel smooth. Moreover, the thick leafy branches are less toothed than those of E. truncatum, and only one-third of their size.

The late Mr. Hamp, of Mawbey House, Stockwell, tried hard to obtain a hybrid between Epiphyllum truncatum and Cereus speciosissimus, but could never succeed. He did, however, raise one good variety of truncatum, named magnificum. Mr. Bruce, also, the talented gardener at Collier's Wood, Merton, tried in vain to produce a hybrid between the E. truncatum section and E. speciosum and others, although he obtained some beautiful hybrids in other sections. It may, therefore, be concluded that E. truncatum will not hybridise with the large-flowered species. More recently, some very beautiful hybrids were raised at the Tooting nursery between the E. Russellianum and E. truncatum, having the symmetrical form of the first, and flowering two months later than the last. The advantage gained by this cross was important, inasmuch as it extended the blooming time quite through the winter, to say nothing of the superiority of form which was secured.

Curtis's Botanical Magazine 66: 3717 (1839)
Epiphyllum russellianum. The Duke of Bedford's Epiphyllum
Curtis's Botanical Magazine 53: t. 2562 (1825)
Cactus Truncatus. Ringent-Flowered Cactus

The Florist's Journal and Gardener's Record, v. 1 (1846)
EPIPHYLLUM TRUNCATUM VIOLACEUM

A more lovely object than the variety of the old and well-known Epiphyllum truncatum, now portrayed, it would be difficult to select, even from the most extensive range of floral forms: in fact it seems hardly possible to conceive anything more beautiful than the rich, vivid, and varied tints which enamel its flowers, produced too in the greatest profusion, with the smallest amount of skill or attention, and at a season when the meanest of flora’s train is greeted with a welcome; it is, beyond comparison, the finest of all winter-flowering plants yet known to us. 

There are a few particulars connected with the cultivation of the original species and the present variety, which deserve to be mentioned. It is usual, on account of the naturally prostrate and dense habits of the plant, to assist its development by grafting on some upright, free-growing individual of the same natural family, when it assumes a very graceful, somewhat pendent character; and by these means is elevated to a height which allows more space for the branches, and brings the flowers to a convenient level with the eye, removing the crowded appearance which their weight on the flexile stems causes them to take when produced on dwarf unworked plants. It is very common to select for this purpose a stock from the genus Pereskia, P. aculeata being frequently employed because of its free, quick growth, and the readiness with which the Epiphyllum “takes” upon it: but we hold this stock to be objectionable for several reasons. It is a climbing, or more properly a creeping plant, which for itself requires support, and therefore not suited to carry the additional heavy head thus placed upon it; besides the stem of Pereskia does not increase in substance, or but very slowly, after the insertion of the grafts, so that it is no uncommon occurrence to find a large luxuriant mass of the Epiphyllum balanced as it were upon what in the contrast looks like a reed: no proportion existing between the stem and the head; and moreover we have found that plants of this species, when worked upon these stocks, are constitutionally more tender, requiring a much higher temperature, both for growing and the production of flowers, than when grafted on some other species of Cactae, which we shall presently mention. The only position in which we can conceive the Pereskia most suitable as a stock for this plant, is when the latter is required to ornament the rafters, or roof of a stove, or to twine and cover a pillar, here the flexuose stems of the former give it the advantage, and by its means the Epiphyllum may be made to put forth its splendid blossoms from any position. 

The standard we prefer, is that offered either by the stronger species of Opuntia, or the erect Cereuses; we have seen magnificent specimens formed in a few years by inserting numerous pieces of the Epiphyllum on a tall stem of Cereus speciosissimus, a method we think preferable to the use of a single scion on the summit, as the effect is obtained in so much less time; indeed it is quite possible to form a large plant almost at once, as pieces containing three or four years’ growth will unite, with a little care, as readily as the single joint of the preceding year’s production. Grafted on either the Cereus just named, or Opuntia ficus indica, the common Indian fig, the Epiphyllum seems to gain much of the robust constitution of its bearer, for it will then grow and flower in a warm greenhouse, whereas upon the stock before mentioned, it insists on the high temperature of a stove ere it will manifest either a healthy appearance, or the least symptom of blooming. 

The routine culture of this plant is of the simplest description; it delights in a rich soil composed of loam, leaf mould, and reduced manure, mixed up with which should be numerous pieces of small potsherds, and a quantity of them placed beneath the soil at the bottom of the pot, that an effective passage for superfluous water may be secured : as the roots of all cactaceous plants are very impatient of excessive moisture. It will require to have the soil renewed once in a year, and to be liberally watered during the summer and while growing, with a reduction of the quantity until the blooming season is past. Observing to keep it continually either in the stove or the greenhouse, according to the description of standard it may be upon; unless indeed the temperature of the greenhouse in winter is kept very low to suit other plants, when it may be necessary to remove it to a warmer atmosphere to assist in the development of its flowers.

The whole of the individuals composing the natural order Cactaceae, are of such extraordinary and variable habitude as to render their classification extremely difficult, and hence the frequent changes of generic terms, so much to be regretted from the confusion to which it leads; the group to which our present subject belongs has been several times separated and again reunited under different appellations, but on this occasion we have chosen to continue the name by which it is most commonly known. Epiphyllum is derived from epi, upon, and phyllon, a leaf (Gr.); in allusion to the station of the flowers upon the leaf-like branches. E. truncatum violaceum was obtained from Brazil in 1838, and is not yet so generally cultivated as it must be acknowledged to deserve. We were kindly favoured with the specimen for our drawing by our esteemed friend Mr. E. A. Hamp, the successful and scientific gardener at Mawby House, South Lambeth. Editor.