The BROMELIAD SOCIETY
|Vol. 1||May June, 1951||No. 3|
Photo by Racine Foster
This spectacular bromeliad when first found in French Guiana was described as Tillandsia splendens by Brongniart over a hundred years ago, in 1845. Among the fanciers of Europe then, it was considered one of the most showy and outstanding of all the bromeliads. It remains today a prized possession among bromeliad collectors. In Europe this has been a favorite plant parent for hybridizing as mentioned by Monsieur Chevalier in his article page 19.
V. splendens is flanked on each side by plants of Billbergia meyerii.
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Airplants need air, moving air. Some require more than others. Those that hold much water in their hearts, such as Canistrums and Nidulariums are not as demanding in this respect as Tillandsias of the xerophytic types, many of which hold no water and get moisture Through peltate scales on the leaves. It is exceedingly difficult, if not impossible, to maintain in good health tinder glass and in pots resting on plant benches such species, as for example, Tillandsia argentea, caput-Medusae, albida, and festucoides. Such plants are easy to grow in good condition when placed in hanging positions in the house where freedom of air movement around them is increased.
Hanging saves much bench space, is the best way to enjoy the beauty of such species with pendant spikes, such as Aechmea Racinae and Vriesia-scalaris, and is in general a method of increasing the ornamental appearance of plants in a glass house. A treatment for ailing bromels is to hang them up. Without any other change in culture a substantial improvement should soon be evident. Increased aeration is like a tonic. It also tends to offset effects of insufficient drainage in the potting material.
A sure way to root a bromeliad off-shoot without risk of losing it by rot is to pot it very firmly in osmunda fiber and to hang up the pot. This method is practically foolproof and is recommended for valuable plants. Do not overpot; better to underpot initially with this method.
With short single-wired hangers the hooks of several pot hangers may be inserted with the rim of a single pot already hanging, a space-saving, compact method; or, pots may be hung in vertical series, each hooked over the respective pot above.
The importance of air to bromels was notably evident in the plants grown in a glass house in Santa Barbara, California, where a large electric exhaust fan in the gable of the house became activated whenever the temperature of the air rose above 78° F. The pots were arranged to permit ample and free circulation of air around, above, and below them. Humidity was manually supplied by spraying around and between the pots and on the floor. The plants flourished with such incredible and unmatched vigor and beauty that it was difficult at first not to attribute this to some secret method or special potting mixture rather than identify the principal benefiting factor as air, moving air.
1179-81 San Vicente Blvd., Los Angeles 24, Calif.
Photo by C. Chevalier
Guzmania X "Victrix" Dutrie|
Guz. lingulata Mez var. splendens Hort.
X Guz. zahnii Hook
By Charles Chevalier
Honorary Keeper of the Botanical Gardens of the Univ. of Liege, Belgium
During the last century, European collections of hothouse plants increased greatly, thanks to numerous species found in exotic countries by hardy and adventurous travelers.
Soon, however, wise and enterprising minds found a way of increasing even these extensive collections: hybridization, a powerful instrument in the hands of an intelligent horticulturist. Professor Edouard Morren (1833-1885) was the first to have recourse to this practice as regards Bromeliaceae, of which he had collected numerous species for the Botanical Gardens of Liege in Belgium. He blazed the trail, and his first hybrid: Vriesia X Morreniana Hort. Leod. (V. psittacina Lindl. X V. carinata Wawra) was created in 1879 and was mentioned in 1882 in "Belgique Horticole" [Vol. 32, p. 287].1
This cross was closely followed by Billbergia X Herbaultii Hort., obtained in 1880 by Maron, a French horticulturist, who crossed Billbergia amoena Lindl. by B. Leopoldii Morr. [B. brasiliensis L. B. Smith, not the earlier B. Leopoldi C. Koch]. From that moment numerous hybrids appeared almost everywhere. Among the experimenters are notably Duval, Andre, Maron, Truffaut, Chantrier, in France and Kittel in Germany, Witte in Holland etc. In Belgium, the Botanical Gardens of Liege were the scene of the birth of many hybrids in the genera Vriesia and Billbergia, thanks to the efforts of my predecessor, Monsier Jos. Marechal and myself. Between the two wars, different and interesting hybrids were obtained by some horticulturists in Ghent, one of whom, Monsieur Louis Dutrie, soon became a master of the art. As an innovator, he produced numerous valuable bigenerics in Ghent; unfortunately, the ravages of the bombardment of 1944, which completely destroyed his establishments and the treasures which they contained, hastened the death of my friend, who was not able to bear this disaster and the loss of all his hopes.
With the exception of Cryptanthus, which long ago furnished Jacob-Makoy, horticulturist of Liege, with a series of hybrids: C. X Makoyanus, C. X Lubbersianus, C. X Osyanus, etc., Billbergia, and more particularly, Vriesia were until about 1930 almost the only plants to produce hybrids. Although very beautiful and infinitely superior to their parents, the first hybrids were rarely found outside the hot-houses of fanciers. The inflorescence of the Billbergia is brilliant but unfortunately short-lived, and the splendour of some hybrids such as B. X Gravisiana Hort. Leod. (B. pallescens Koch and Bouche X B. Maxima Ch. Chev); - B. X Chevalier Hort. Leod. (B. thyrsoidea var. fastuosa Morr. X B. amxima Ch. Chev.); B. X Professor Monoyer Hort. Leod. (B. Leopoldii Lind. X B. thyrsoidea var. fastuosa Morr.), created in the Liege Botanical Gardens; - B. X Breauteana Andre (B. pallescens Koch and Bouche X B. vittata Brongn.) etc. obtained in France by Ed. Andre, does not compensate for this fault in the eyes of professional horticulturists. I have heard that the Botanical Gardens of Vienna also obtained some beautiful hybrids, but I am not acquainted with their names nor with their origins.
The B. maxima Ch. Chev., mentioned above, and which I have used to create beautiful hybrids, is an old species, remarkable for its size and the beauty of its inflorescence. It was cultivated for a long time in the hot-houses of the Liege Botanical Gardens under the dame B. species maxima Barbacena. The name "Barbacena" probably is derived from its place of origin in Brazil. Having done some research on it, I found that this species had never been described. In order to fill this lack, I gave a complete description of it in the "Journal de la Societe National le d'Horticulture de France" (May, 1931).
If the inflorescence of the Billbergia is ephemeral, that of the Vriesia, (on the contrary) is long-lived, and gives this plant a much higher market value. Successive hybridizations have agreeably modified the primitive types, which are, generally, rather dull in colour; their shape has improved, and the dimensions of the spikes have taken on unusual proportions. The plants themselves, having become more freely-blooming, are easier to cultivate.
Hybrids are only found, so to speak, in the section Euvriesia. Some kinds, particularly V. Barilletii Morr., V. carinata Wawra, V. Duvaliana Morr., V. incurvata Guad., to which we should add V. psittacina Lindl., V. splendens Lem., V. Saundersii Morr., V. Rodigasiana Morr., V. Van Geertii Hort. Duval, have marked their descendants with a special stamp which discloses their influences even after several generations.
The V. Barilletii has played a dominant role in the robustness of the plants and in the improvement in the shape of the spike. The influence of V. carinata Wawra (V. Brachystachys Reg.) is shown by the elegance of the inflorescence, and in the bracts, which are more colourful, closer together and more enveloping, with their tips markedly curved like a parrot's beak. To this group belong V. X leodiense Hort. Leod.; - V. X Closoniana Hort. Leod., both bred from a cross between V. X Morrenii and V. Barilletii; - V. X Mariae Truffaut; V. X Gravisiana Hort. Leod. (V. Barilletti X V. splendens) with a handsome, colored spike narrower and more pointed than its predecessors; also V. X Mephisto Hort. Leod. (V. hyb. unnamed by V. cardinalis), one of the darkest, with a broad erect spike, and blood-red bracts. By crossing V. X Mephisto by V. Pastuchoffiana Glaz., a species with big green leaves marked with darker green irregular lines, I obtained V. X Papa Chevalier Hort. Leod., a fine hybrid resembling the male parent but having a scape terminated by a beautiful dark red-purple triangular spike.
In 1890, by crossing V. carinata Wawra with V. psittacina rubro punctata Hook., better known under the name V. Krameri Hort., Duval obtained V. X cardinalis Duval. This is a small plant, interesting from a commercial point of view because of its rapid growth and its lovely cardinal-red bracts. It is to this hybrid, and to the influence of its male parent, V. Krameri, that horticulture owes the red colouring of a good many beautiful hybrids now being cultivated.
V. incurvata Guad., V. Duvalii Morr., and V. Van Geertii Hort. Duval all contributed to certain Vriesia hybrids which are easily recognized by their incurving bracts, and by the shape of their spikes which are oblong, more bulging, and thicker. Principally to be noted are: V. X gloriosa Duval (V. Barilletii X V. incurvata) and its offspring: V. X Poelmanii Hort. (V. X gloriosa X Van Geertii), a medium sized plant with stout spike, and enveloping bright-red bracts, widely cultivated in Ghent. Particularly notable among second-generation hybrids are V. X Menelik Hort. Leod., with bracts of a violet-red, almost black; V. X Wallonia Hort. Leod., a vigorous plant with a spike 45 centimeters in length, and red bracts shaded with yellow.
Vriesia with panicled floral stems are very rare; they have, however, the advantage of being more elegant and decorative. During my stay at the Liege Botanical Gardens, I tried to improve in this direction cultivated Vriesia hybrids. Even before that, different branched shapes had been obtained, notably: V. X Kitteliana Hort. (V. Barilletti Morr. X V. Saundersii Morr.) a vigorous plant with an oblique scape and rather dull bracts, brownish-red on a background of orangeshaded yellow; V. X Vigeri Duval (V. Rodigasiana Morr, X V. X cardinalis) a sweet little plant with a scape bearing lateral secondary spikes, cardinal red in colour.
These two hybrids and their offspring, which I used very widely, gave me some lovely varieties with well-branched floral stems. Of these I will mention only: V. X Prince Leopold, a stout, well-branched plant with widely spaced bracts of salmon-pink washed with yellow; - V. X Polonia, one of the handsomest, its bracts carmine-red at the base; - V. X Belgica, vigorous, with a strong scape composed of six to seven spikelets with yellow bracts; - V. X Prince Charles, a strong, well-branched plant with salmon-pink bracts; - V. X Croix d'Honneur, a small plant with the bearing of V. X Vigeri, with a well-branched scape, and widely spaced bracts of red washed with violet; - V. X Gerbe de feu, a vigorous plant with a high scape, stout, branched and with red bracts; etc.
The fecundation of V. Lubbersii Morr., a vigorous plant 70 centimeters high, with reddish-green bracts, by V. X Mephisto, gave me V. X Africain, a fine stoutly spiked hybrid with richly coloured bracts, of a lovely brilliant red-purple, almost black. Unfortunately its branched character is not constant.
I note, in conclusion, a very vigorous hybrid with colorful bracts, however the stiffness of the inflorescence, although well-branched, prevents it from being graceful. It is much cultivated in Ghent under the misleading name of V. viminalis erecta. I do not know its origin, but I have reason to believe that V. X Poelmanii had something to do with its creation.
Many hybridizations have been attempted in Ghent, and by myself, in order to obtain Vriesia having at the same time the beautifully veined and streaked foliage of V. tessellata Morr., V. fenestralis Lind. & Andr., V. hieroglyphica Morr., and the handsome, colourful spikes of the V. hybrids. Unfortunately, the results have been disappointing. In general, the leaves lose the streaking almost completely, and the bracts do not acquire a sufficiently rich colouration. V. Pastuchoffiana Glaz. alone seems to possess the property of transmitting the handsome marbling of its leaves to its descendants.
My much-lamented friend, Monsieur Louis Dutrie, wishing to leave the beaten track, and to interest fanciers in the production of new plants, inter-bred different species of Nidularium, Aregelia2, 'Guzmania, and Aechmea. Later he successfully attempted crossings between different genera. From the first he was classed among the cleverest hybridizers of Bromeliaceae. It is also interesting to note that these crossings, which produced original, hitherto unknown, and decorative forms, also demonstrated the possibility of obtaining some vigorous plants-many more than by the planting of slips, and this after only twenty-six to thirty-six months of cultivation, sometimes even less.
Nidularium X Chantrieri Andr. obtained in 1895 by Jules Chantrier'3 of Mortefontaine (near Paris, France) from the crossing of N. innocentii Lem. and N. fulgens Lem., is a magnificent hybrid with coloured leaves. It was the only one known, and in spite of the improvements observed in Dutrie's new hybrids, it has not yet been surpassed. Notable, however, is: Aregelia* X decora Hort. Dutrie, 1937 (Aregelia* concentric var. Plutonis Mez X Areg. princeps Mez), a perfectly formed plant, the leaves short, wide, and olive-green spotted with darker green, and the bracteal leaves shaded bright pink. Also notable: Nidularium X Francois Spae (N. striatum Hort. Bull. X N. fulgens Lem.), with long narrow leaves of a brilliant bright green spotted with dark green, and bracts of a lovely cool flesh-pink. This is much cultivated in Ghent. There are many other interesting hybrids.
Monsieur L. Dutrie was particularly successful with Guzmania, and obtained some remarkable hybrids. The most interesting is: G. X lingulzhanii Hort. Dutrie, obtained by the crossing of G. lingulata Mez var. splendens by G. (Caraguata) Zahnii Mez. From this hybridization came several forms of exceptional quality which received flattering awards at the 1939 "Meetings de la Chambre Syndicale des Horticulteurs Belges at Ghent. All these forms are distinguished by the large size of the plant, the richness of the foliage, and by the abundance of the inner leaves, the latter almost as colourful as the bracts which are rather bright red. Monsieur L. Dutrie gave the name "Insignis, Chevalieri" to the most distinct varieties (80 centimeters in diameter), and the name "Victrix" to the handsomest, etc.
The genus Aechmea was particularly worked on. Many kinds, but principally the Ae. fulgens Brongn. and Ae. fulgens discolor Beer, Ae. fasciata Bak., Ae. Chantinii Bak., Ae. ramosa Mart., Ae. caerulescens Bak., etc., were crossed with each other or with other species. One curious discovery was that Ae. Chantinii, from which no results had been obtainable by auto-fecundation, gave when fecundated by Ae. fulgens discolor a whole series of really remarkable plants. These had leaves of every shade from olive green to reddish-brown, and thickly flowering capitula, well separated above the foliage, presenting a whole gamut of warm, bright colours, from canary yellow, through orange and salmon-pink, to coral red. These are designated under the name Ae. X fulgo-Chantini Hort. Dutrie.
Ae. fulgens discolor when fecundated by Ae. ramosa gave: Ae. X fulgo-ramosa Hort. Dutrie. These plants are stronger than the female parent plant, and have green or brown leaves with large, upstanding, well-branched panicles, whose flowers are followed by orange-yellow berries about the size of a pea.
The hybrid produced from the fecundation of Ae. Chantinii by Ae. fasciata is matchless. The plant is stronger than the male parent, with leaves fifty to sixty centimeters long and eight centimeters wide, stiff, farinaceous, ribboned with white on the top. It has a very straight, long lasting floral scape lifting above the foliage a strong cone-shaped panicle, twenty centimeters wide, and with long bracts of a pretty salmon-pink. Notable among many others is Ae. X fulgo fasciata var. tricolor Hort. Dutrie (Ae. fasciata X Ae. fulgens discolor), a plant with leaves that are often brown on top with a brownish-violet underside and shiny. The scape is terminated by a tight capitulum, with the white ovaries blending with the blue flowers and pink bracts.
Bigeneric hybrids are extremely rare. In 1880 Lemoine of Nancy (France) crossed Guzmania Zahnii Mez with Vriesia splendens Lem., and produced the hybrid known under the following names: X Vriesia magnifica Morren, X Caraguata* magnifica Hort., or X Tillandsia magnifica Hort. This hybrid, very difficult to raise, has probably disappeared from present day cultivation.
On his side, Monsieur L. Dutrie succeeded in crossing Vriesia incurvata and Guzmania Zahnii several times, and Guzmania lingulata splendens and G, cardinalis, fecundated by several hybrid Vriesia with single or branched floral stalks. He described them under the generic name of "Guzvriesia" Hort. Dutrie. All are characterized by great vigour, and by numerous brown or red shaded leaves which form thick, perfectly shaped rosettes. The floral scape is very strong, and very erect, carrying a strong, intensely colourful spike. The inflorescence of one plant is formed by a group of close spikes, conical, fifteen centimeters wide at the base, and twelve centimeters high, with red bracts.
Attempts at hybridization between Tillandsia and Vriesia have met with very little success, although they are closely related. I have, however, had the good fortune to achieve some crossings of one, X Vrieslandsia Prof. Bouillenne Ch. Chev., described in 1931, which was obtained by fecundating Vriesia X Souvenir de Jos. Mawet by Tillandsia caespitosa Chain. & Sehl.
Monsieur L. Dutrie also produced other kinds, notably: Androlepis Skinneri Brongn., which, when fecundated by Aechmea fasciata gave X Androlaechmea crateriformis Hort. Dutrie, a vigorous plant with green leaves which are farinaceous and erect, tubiform for two thirds of their length, and then recurved, thus resembling a large vase. The inflorescence resembles that of Ae. fasciata but is a darker red.
Although adjoining and generally designed in horticulture under the name of Nidularium, the Aregelia* (Neoregelia) and the Nidularium properly so-called, differ however in the position of the florescence in the heart of 'the leaves. A certain number of crosses were made between the species of these two genera; unfortunately the plants grown from seeds sown in 1942 were destroyed by bombing before having had time to bloom.
Crossing which included Aechmea on one side and Aregelia2 and Nidularium on the other side, succeeded perfectly, but though they offer a certain scientific interest, are not worth preserving as commercial plants. In general, the inflorescence is very similar to that of Aregelia*. - It is supported by a longer peduncle, is separated from the heart of the plant, and is often composed of several short, fat spikes, very crowded, and of an unattractive colour.
In spite of my intention, this review of hybrid Bromeliaceae obtained in Europe is neither brief nor complete. It does, however, give a general idea of the attempts which have been made to create new forms by hybridization.
It is deeply distressing that most of the hybrids born in Ghent on the eve of the war, or at its beginning, have been destroyed. Fortunately, most of the crossing succeeded beautifully and the most fertile among them can be remade, with this time the certainty of success affirmed by experience. The way is open for fanciers of Bromeliaceae.
It would also be interesting to study the reciprocal action
of generators upon their descendants, but that must be left for another time.
Our distinguished Trustee from Argentina, Dr. Alberto Castellanos has recently sent as a gift to The Bromeliad Society a set (10 booklets) of his valued contributions on Bromeliaceae.
These contributions are botanical papers which contain the descriptions of the Argentinian bromeliads, many of them new species described by him. The Society is very fortunate to have these as many are out of print. They have been published in Argentina over a period of years from 1925 to 1945 representing a great deal of work and research on the part of Dr. Castellanos in this great family.
In addition to these Contributions Dr. Castellanos's most outstanding botanical work is his monograph on five families of the Order Farinosae which includes the Bromeliaceae. This work is contained in Tome Three of "Genera et Species Plantarium Argentinarum." This large volume, fourteen by twenty inches, is the most elaborate single work ever done on Bromeliaceae. It contains fifty-six full page colored plates as well as nearly 200 drawings and photographs. A copy of this volume is in the possession of the President of this Society and will sometime later become a part of the Society's Library.
Photo by J. G. Bacher
A native of southern Brazil, Paraguay, and Argentina is one of the most common of all bromeliads in horticulture. This fifteen-year-old plant should be proof enough that bromeliads make good house plants.
J. G. Backer
It is amazing to realize how few house plants are able to endure the modern homes and apartments of today. Even the greenhouse men of the northern states are usually hard put to offer a truly resistant plant with the assurance that they will thrive more than a few months at best.
Having grown house plants of all sorts for over 50 years, it is a sad awakening that the plants of yesteryear are no longer of much use today because they fail to live normally as they did in years past. Why should that be, most readers feel like asking. Here is my explanation: it is one of the results of modernization in the heating of homes where formerly stoves were used and the heat indoors fluctuated greatly from one extreme to the other, yet a basic moisture remained in the air, so essential to the welfare of plants. Boston Ferns were widely used the nation over as house plants, whether the fringed or plain leaved sorts they lent a bit of grace and charm highly desirable everywhere. While today, in the plant markets of our cities one seldom sees them anymore. Although the ferns are as handsome as ever they will not tolerate the constant dryness of air now prevailing in uptodate homes regardless of how much water you pour on their roots trying to overcome the aridity of the air. So here is good news to readers who wish to know what sort of plants will thrive under those conditions for the Bromeliad family representing a large group of air conscious plant species is now the modern source of house plants that can make good if given a thorough trial.
I will mention at this time only one form that has given a marvelous account for its robustness and ability to make itself happy under home conditions in late years. That plant is quite well known, especially in southern California, where it frequently grows outdoors in the garden and will put up with occasional frosts that come along. This plant is best known under its proper name of Billbergia nutans, although a variety of common names are given it by the public of which "Tropic Tassel" seem to me most applicable.
As I have grown Billbergia nutans over a long period of years, let me cite an experience of my own that reveals as well as anything can, its innate hardiness. Some fifteen years ago I happened to advise a lady complaining about the frailty of Boston Ferns that she would have far better luck with Billbergia nutans, the Tropic Tassel Plant. She half heartedly purchased a small plant and went home. Naturally, I forgot all about it until twelve years later my phone rang and this same lady insisted on talking to me. What a surprise I got, for she asked me somewhat coyly if I ever traded in old plants. Then she explained that twelve years ago she bought a plant from me which now had grown too large for her rooms and the ability to handle. She would like to have a good Fuchsia for her garden instead! This request puzzled me no end for never in all my fifty years experience had I heard of a house plant being any good after twelve years in an average home, but my curiosity induced me to say yes I would trade if she brought it in. Next day (it was mid-November) in comes my old customer with the Billbergia nutans over-flowing a ten inch pot. It was in perfect condition bearing perhaps 100 crowns of leaves. I promptly allowed her to choose any specimen Fuchsia I had and she went home happy over the bargain.
As this plant was rather large it had to remain in a geranium house where a temperature of 52 to 54 degrees prevails as well as being very sunny. Little attention was paid to it until it came into flower about the 10th of January when it was covered with the long drooping tassels of flowers for over three weeks right during the darkest season of the year in our climate. This truly was a sight to dream of. Never before had I seen such a large specimen in bloom. After it was done flowering it, was left alone and the following winter moved to a warmer house where it flowered the next season, fortuitously, during the Christmas season. For three years now this plant has not been transplanted and had no further care than a daily sprinkling over head during the summer season. Now I have sold it for the second time to a down-town club room! So much for this bromeliad as a satisfactory house plant.
1920 N.E. 7th Ave., Portland, Oregon
Mr. J. G. Bacher was at one-time many years ago a student of M. Charles Chevalier when he was instructor in the Swiss Garden School at Geneva. Mr. Bacher, now a horticulturist in Portland, Oregon, says of M. Chevelier: "I correspond occasionally with friend Chevalier and have sent him a large collection of photos which he uses for illustrating his many writings which has been his line of work since being retired as Director of the Botanical Garden at Liege, Belgium. He is nearing his eighties, so it is marvelous that he can preserve his faculties and do so much in fostering the spirit of horticulture in the French language of Belgium. He is a prince of a fine man in every respect and has written something like 18 different volumes on horticultural subjects."
This is a sixty-four dollar question from California! Actually, of course, all bromeliads do flower, even if it takes them 150 years to attain that achievement, as in the case of Puya raimondii.
Most of us would prefer not to wait 150 years and so become a bit impatient when some of the species do not flower. One of the most provoking experiences is that certain species seem to flower regularly for one person or in one section of the country, yet, that same species may rarely ever flower in another area. Of course, there is a reason but we may not be able to explain it. There are so many conditions that enter into this problem that no one can give the specific reason in each case.
We do know, however, that some species are much more tolerant than others to different growing conditions, such as light, and temperature and this problem often becomes one of local conditions. Certainly, the water question is an important one and rain water is unquestionably the best, although not always easily obtainable. Water on the neutral to acid side is best, however, many aechmea, neoregelias, billbergias etc. will tolerate water slightly on the alkaline side.
Vriesias certainly want acid water and the ones that do best with me are those that I put outside in a shade house where they receive plenty of rain. Also, I always pot vriesias in osmunda alone, and almost all other bromeliads in an acid medium such as leaf-mold, german peat, osmunda and sand. I think that osmunda could be used for practically all bromeliads but it should not be allowed to break down to a soggy "sweet" mass.
Look and feel the texture of your plants. If the leaves are stiff, spiny, spotted or covered with gray tomentose scales they will most likely need much light and air. If the leaves are glossy and thin as with most vriesias they will need more syringing, shade and protection from too many air currents.
Light hours, cool temperatures, dry spells, rainy moist seasons are all natural causes for having normal flowering seasons for the different species. However, any one of these conditions along with the improper chemical content of water or food may cause the plant to continue to grow year after year, produce offsets and otherwise appear healthy but it may not produce flowers. These problems are generally local and may or may not be solved by the grower.
I, myself, for years, have been unsuccessful in even growing Guzmania Musaica in my greenhouses. This species just doesn't like our conditions, water or situation. I thought it might be altitude but when I found it growing natively in Colombia at 4,000 ft. above sea level and then in another area, ten feet above sea level, I decided that elevation was not the cause, but unfortunately, I have not yet found the answer for its happiness, so far as my location is concerned, although it grows happily and flowers in St. Louis, Baltimore, Washington and New York.
I have some vriesias which I collected in Brazil eleven years ago. They continue to grow but do not increase in size nor do they bloom!
As a corrective suggestion I would say to try different potting mediums than that you are using now ... different light, a new location in your greenhouse ... a different procedure on watering, a different feeding mix. A change in any one or more of these conditions may be the reason that will bring out flowers on your bromeliads.
Flowering of bromeliads can be induced in many cases by the use of certain gases and chemicals; I have been working on this problem for several years. This past winter I made a startling observation and I am hoping to be able to give some definite information on this subject in the near future, but first, certain planned experiments will have to be made.
M. B. F.