Jour. Royal Hort. Soc. Vol. LVII. Part 1. January 1932
The genus Amaryllis including its bi-generic and other hybrids and crosses.
by A. Worsley

[Read April 28. 1930; Mr. F. A. Bowles, M.A., F.L.S., F.E.S., V.M.H., in the Chair.]

I HAD intended to treat of the exotic Amarylliae, but the title given covers a field quite wide enough for a single paper, and enables me to deal with many details which would otherwise have bad to be omitted. I shall therefore restrict myself to the genera Amaryllis and Brunsvigia as defined by Baker, and to Crinum in part.

I have purposely cut out the matter contained in the mass of literature referred to at the end of this paper, which anyone who desires may study at leisure. Hence you must not expect to find here a general résumé of the subject. It is rather an amplification of certain sections already published. Amaryllis has been in cultivation in our gardens for 220 years, and a Brunsdonna (but not under that name) was shown in flower before the Royal Horticultural Society on August 18, 1875. In our JOURNAL, 51, pp. 64-67, you will find all that was then known as to Brunsdonnas both from an historical and a cultural point of view. There is little doubt but that, up to the end of last century, all Brunsdonnas in British gardens originated in Australia (Bidwell) excepting (at most) two natural hybrids introduced from S. Africa, but all of which appear to have died out under cultivation in Britain, These Australian hybrids came to us about 1875, and were in 1889 known under the name of Amaryllis Arbuckle's var. and were distributed from the Royal Gardens, Kew. I have recently had two forms sent me straight from Australia which have not flowered here. In the present century Mr. John Hoog, of Messrs. Van Tubergen, and myself have both raised hybrids between Amaryllis and Brunsvigia Josephinae. Hoog raised hybrids both ways, and those he raised on Brunsvigia are very dissimilar plants from those raised on Amaryllis, thus perplexing (in this single instance at least) those pundits who declare that whichever way a hybrid is raised it must bear the same name, and perplexing also those who deal in these plants, and who must follow the accepted nomenclature however much it may be contradicted by the appearance of the hybrids themselves. These Amaryllis grow in warm temperate regions, and their flowering is erratic in cool temperate regions. Brunsvigias and Brunsdonnas are still more shy. No one has solved the problem of why this is so, but the shortened period of heat and of sunlight must be given due importance. Irregular rainfall also interferes with the normal growing and resting periods. But there is some other factor also, for, when planted out under glass, their flowering is still shy and erratic. Nor can we be sure that Amaryllis are always free-flowering even in warm temperate areas. I was told that they flowered freely every year in Grand Canary, and on inquiring about how many flowered in a certain plot of garden in an hotel patio I was told about a hundred. But on digging down a few inches I found a tightly packed cuirass of bulbs, so that there must have been some thousands there. It is probable that some substance is lost to the bulb in producing flowers, and may not be replaced during several years of normal growth, and this period is extended in our climate by climatic uncertainties. I have found that good seasons for the flowering of ordinary Amaryllis out of doors have not occurred more than three times in the last 26 years (say once in 9 years) and that on several occasions 3 bad years have occurred in succession. Under glass, or at the base of a heated wall, flowering is by no means so erratic, In the extreme S.W. of England Amaryllis Belladonna has become a kitchen garden border plant, but only a small proportion flower most years. The var. rubra major (sent out by Van Tubergen) is the most reliable flowerer in my garden, and is one of the most beautiful of all Amaryllis. Under glass most bulbs of this variety will flower every year. Brunsdonnas and Brunsvigias should not be grown out of doors in England except in specially favoured coast districts of the S.W., and in picked places there. In the Mediterranean area the flowers are much used in churches for altar decoration, and on that account only have been planted in many Catholic countries. This accounts for the rapid spread through the warm regions of the world more than a century ago. The coloration of the basal sheath to the pseudo-stem is a sure indication of the extent and depth of the crimson colour which will appear in the flowers. If this basal sheath has no ruddy colour, the plant is an albino. Hybridization has been effected with two species of Brunsvigia and with Crinum Moorei; some say also with Lycoris, but my efforts in this last direction have hitherto shown no result. So many hybrids raised with Brunsvigia prove that these two genera have been reconciled, but this occurred only twice with Crinum and both times with C. Moorei. On this slight basis one can hardly speak of reconciliation between the two genera. Hybridists should try to secure a hybrid between Amaryllis and Nerine Bowdenii, although the flowering periods do not quite coincide.

Decurrency of Varieties.

Some half-dozen named varieties have been put on the market by Dutch firms (some of them over half a century ago). In comparing those which may flower to-day with the plates published long since, we cannot see any signs of decurrency. But it is doubtful if this absence of decurrency applies to Brunsdonnas. We all know how the Hyacinth gives one splendid spike of flowers, and that the same bulb never again produces such a fine spike. This result is produced by preventing the young bulb from flowering until it has had time to grow to its maximum size. Brunsdonnas do not require any art to prevent their flowering. The inclination of seedlings is to grow for 20 to 25 years (in our climate) to reach their maximum size of bulb, and then to carry a splendid scape of flowers. Probably the same bulb will never again carry such a fine scape—although this is not an invariable rule, for occasionally a seedling bulb will carry a precocious flower spike before it has reached its maximum growth of bulb, and a finer scape in some subsequent year, but this is a rare occurrence. We cannot, however, call this decurrency in any permanent sense, for the offsets from Brunsdonna seedlings will in their turn, and when they have reached their maximum growth of bulb, produce scapes as fine as those of the original bulb.

On the other hand, I have not, of recent years, seen any specimen carrying 30 to 40 flowers to the scape, such as has been recorded and figured in the past; but this may be due to climatic conditions having been of late years unfavourable.

Brunsvigias reproduce themselves freely from seeds, but very sparingly indeed by offsets. I have cultivated very many, and can just remember one offset bulb being formed. Brunsdonnas, on the other hand, produce a fair number of offsets, and by this means will double their number, even from the seedling stage, in about 12 years. Certainly one offset a bulb per annum, even for big bulbs, is above the average. Brunsvigia Josephinae takes about 30 years to flower from seed in England, Brunsdonnas from 8 to 22 years, and Amaryllis Belladonna 5 to 6 years. Crosses back between Brunsdonna and pollen of Amaryllis are inferior to Brunsdonnas. Those which flower in 4.5 to 6 years will be barely distinguishable from Amaryllis, but those which flower subsequently will show at least some characteristics of Brunsdonna, and may be worth cultivating, but in general they will be good for Amaryllis, but poor Brunsdonnas. Brunsdonnas certainly do not flower with us on an average of more than once in 8 or 9 years. Typically they should carry 20 or more flowers to the scape, but if a bulb can be induced to flower more often, it will sink back into carrying umbels of only 8 to 12 flowers. I have seedlings which have carried up to 28 flowers to the scape, but not often; 40 flowers to a scape are on record. Fully grown bulbs of Brunsdonna may measure 4.5 inches diameter, being thus intermediate in size between Amaryllis and Brunsvigia Josephinae.

The variety Amaryllis Belladonna rubra major carries 12 to 18 flowers to the scape as compared with the typical 8 flowers carried by A. Belladonna, They are brilliantly coloured, but rather narrow in their segments compared with their length of limb. As a seed-bearer this variety is valuable, as I have known a single fruit produce 56 seeds, of which 42 seemed perfect.

Generic Affinities.

There is no doubt but that Amaryllis and Brunsvigia are one genus, but I do not think we have got far enough to include Crinum in it.

The evidence for the former rests upon a large number of hybridizations effected by many hybridists and involving at least two distinct species of Brunsvigia. The evidence for including Crinum in the same genus rests upon two crosses affecting one species of Crinum only.

Amaryllis and Brunsvigia Josephinae have been crossed many times. I have effected hybridization both ways every time I have pollinated them. Bidwell, in Australia, also hybridized Amaryllis with B. gigantea both ways.

As to crosses with Crinum, I tried several species of Crinum, of which I once had a large collection. On sixteen occasions (many stigmas being pollinated on each occasion) I placed Crinum pollen on Amaryllis without raising a single fruit. On five occasions I tried Amaryllis on Crinum without raising fertile seeds, but on four of these occasions some sort of fruit was formed and what looked like seeds. As the most beautiful Crinums rarely produce seed in England it may well be that we may presently be presented with more evidence of affinity between these reputed genera.

Dr. Ragioneri of Florence has placed on record hybrids between Amaryllis and Lycoris, but I have seen no record of verification by the flowering of these seedlings.

At Isleworth neither Lycoris aurea nor L. squamigera has ever carried seed, but on ten occasions I placed Lycoris pollen on Amaryllis. On three of these occasions fruit was formed, but no fertile seeds resulted.

Some day Amaryllis and Acis will be reconciled. I placed Amaryllis pollen on Acis autumnalis [Leucojum autumnale] on four occasions, raising fruit every time, but no fertile seeds.

Crosses among Amaryllis of the Belladonna Type.

I know of none of these crosses of any merit raised in recent years. I have raised some, but none of them showed any marked advance on its parents, but often retrogression. It looks as though we possess optimum types of Amaryllis and that no further advance is probable unless by hybridization with pollen from the bi-generic crosses.

Bi-generic hybrids.—These have been so carefully recorded in JOURNAL R.H.S, and other publications that there is no need to repeat here what you can find there.

Amaryllis Belladonna rubra major.—Mr. W. Watson believed this bulb to be a Brunsdonna. We examined it together and noted the very well developed pseudo-stem, but I did not feel able to agree with him. Since then I have only noted that it carries more seeds to the fruit than does any other variety of Amaryllis Belladonna which I have ever examined in fruit. Forty-two good seeds in one fruit is an extreme number compared with some 8 to 12 which A. Belladonna usually bears. It was originally obtained by the late Mr. Elwes as A. blanda, from some unrecorded source. It is certainly worthy to be grown by all lovers of this class of bulbs.

Colour.—The presence of colour (even if such colour may, as some say, be merely an index of the presence of other characters, rather than an element vital to the plant) is one of the first indications of health noted by the gardener.

A slight variation in colour is to him a sign of something wrong, a variation often so slight that it would pass unnoticed by anyone who did not live with his plants. He picks that plant out, examines it, and, if he is wise, removes it to the hospital. In a general sense this is true of all organisms. The Cactus which assumes a pruinose colouring is too dry at the roots, and is striving to conserve whatever moisture is left to it by covering its stems up in a waxy exudation, and thus limiting evaporation. In humans, the coloration of the skin is an index to the health of the body. But is this coloration a mere index to the presence of other characters, or is it an index of the preservation, or of the decay, of processes vital to the life of the organism? I lean to this latter thesis in the main, but of course one must take species and kinds sui generis.

The question of albinism cannot now be discussed, but only coloration, and upon the connexion between coloration and vitality I have some interesting notes. The so-called albino Brunsdonnas have proved to be more delicate than the coloured forms. Purplish-rose is the colour shown by typical Brunsdonnas. Some colour segregation is visible, for, towards the bases of the flowers, the yellow is segregated out from the red component of the purplish-rose, and this latter colour is concentrated towards the apices of the flowers. Let us follow the incidence of this purplish-rose colour in the seeds and we shall find that it is in them an evidence of vitality. Taking ripe fruit of Brunsdonnas and Amaryllis, I divided the seeds out according to colour, discarding seeds of doubtful fertility or much undersized. I found half of them pink of varying intensity, a large number white or practically colourless, and a few of a full purple colour. On the maturity of the second leaf, these results were disclosed among the seedlings as follows:

     Eighty-six seeds had produced 65 seedlings.
     All the purple seeds had grown into vigorous bulbs exceeding in growth all the others.
     Ninety-one per cent. of the pink seeds and 51 per cent. of the white or colourless seeds had produced bulbs.

Another fruit was similarly dealt with. Purple was absent from the seeds and the average percentage germination was lower, but followed the same scale—50 per cent. of the pink and 33 per cent. of the white seeds producing bulbs.

How much of the coloration of seeds is due to some of them receiving more sunlight than have others, and to what extent such surplusage of light has induced an excess of vigour in the seeds concurrent perhaps with a deeper coloration, would require a fresh set of experiments. But the prima facie view is that colour even in seeds "is an index of the preservation, or of the decay, of processes vital to the life of the organism."

Cultivation—What the books say is not of much help to the cultivator of this class of plants. Had they proved of much help we should not record so many failures among cultivators. What is to be found in the books is often correct in a general sense, but the trouble arises in the application of this learning to particular cases. Climate, soil, situation, the sorts experimented with, whether the bulbs have been cultivated over here long enough to get acclimatized and to have altered their period of growth to suit our seasons, or whether they are just landed perhaps from the Southern Hemisphere; all these things contribute to success or failure. In order to meet the varied needs of particular cases, some modification in the formulae of the books is needful, and what modification in procedure, or reversal of the instructions given, will suit each need cannot be learned from rules, but only by experience. It is the old trouble that the conceived "universal" can never be completely represented in the present "particular."

Nevertheless. I must say something more definite about cultivation, Amaryllis are not particular as to soil, provided it is porous. Gravelly or sandy soils are appreciated. We have been told that dry situations best suit the genus. But the only group of Amaryllis of which a great part died out at Isleworth was planted in a particularly dry place; and the fact that the genus has become a kitchen garden border plant on the coasts of Devon and Cornwall is proof that double the rainfall of the London area is no detriment to its cultivation.

The emission of the flower-scape from the root-stock occurs synchronously with the emission of new roots from the basal disk. This is one of the results of autumn rains, which, if unduly delayed, may keep back the emission of the fiower-scape until the temperature has fallen too low for its growth. This is one of the causes why effete flower-scapes are often flung out of the bulbs in the following spring. Hence, if planted at the base of a wall or under glass, a series of floodings should be given to Amaryllis in the earliest days of August. Some seasons the bulbs outside get all they need, but rarely. Of this I am sure, and I think that an occasional flooding in mid-July also would be beneficial. It is noticeable that Amaryllis grown at the base of a wall devoted to Peaches often flower better than elsewhere, and in this position they get a July flooding or two. But Brunsvigias enjoy a longer drought period than do Amaryllis, and want more roasting to induce flowering. The roots of Amaryllis are deep-stricken, and in S. Africa receive torrential rains when it does rain. When we administer water our object should be to flood, so that the bulbs may soon become dry again, but the roots remain damp for a long time. On the Continent there are areas where, on account of the level of underground water, the ground is always damp about 2 to 3 feet below the surface. The dry layer above this is of a sandy nature. Some of this land has had glass-houses built over it, and the Amaryllids planted in the ground. Under this treatment they are never watered, and the trapped sunheat induces flowering to an extent which no other method of cultivation has achieved. But such conditions cannot well be imitated elsewhere. We can, however, do something to simplify and improve our methods of cultivation under glass by raising a bed about 2 to 3 feet high on walls in any unshaded glass structure from which frost can be just excluded, leaving the coping of these low walls projecting a few inches above the surface of the bed, and supplying efficient drainage and a sandy surface to the bed. Bulbs of such genera as Amaryllis, Brunsvigia, Lycoris, Nerine, etc., planted in such beds, with a minimum of labour, flower with a frequency and vigour which cannot be approached by similar plants grown in pots.

Relative Hardiness.—Herbert said that his Amaryllis blanda—which was undoubtedly a Brunsdonna—was more tender than Amaryllis, and that if once cut by frost its injured leaves would not continue to push themselves out from below as do those of A. Belladonna. There is no doubt about the relative tenderness of Brunsdonnas, yet I have found that their leaves will continue to grow after they have been blackened by frost almost to the ground level.

Brunsvigia Parkeri alba is the most tender of them all, and the form B. Parkeri Tubergeni has the hardiest foliage: its leaves will actually recover in toto from being frozen through. But the experiment is like playing dice with providence. Some Nerines are hardy in situations which suit them. This is undoubtedly the case with Nerine Bowdeni, and I can recommend the free-flowering N. flexuosa alba as hardy in similar places.

As to bibliography, records exist in:

JOURNAL R.H.S., Nov.,1909, p. 226 et. seq.
    "      "      51, "The Brunsdonnas," pp. 64-67.
Gard. Chron., July 29, 1850, p. 470.
    "      "      Feb. 6, 1909, p. 92.
    "      "      Jan. 23, 1929, p.57 (Plate).
    "      "      Nov. 6, 1925, Brunsdonna Parkeri.
    "      "      New Series, Vol. 4, p. 243.
    "      "      Feb. 11, 1928, pp. 99-101 (Plate), Crindonna Corsii,
Garden, Nov. 19, 1898, p. 414.
         "      VIII, p. x66.
Gardening Illust., Oct. 3, 1925, p.597 (Plate of Brunsvigia Parkeri alba).
Herb. Amaryll., pp. 278-9, 422, 425.
4th Intern. Conf. on Genetics. Paris, 1911.
Bot. Mag., t. 1450. Amaryllis blanda
Paxton's Mag., 1882 (Plates of Amaryllis blanda).