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ORCHID SPECIES CULTURE Charles and Margaret Baker Laelia speciosa (H. B. and K.) Schlechter AKA: Bletia speciosa Humboldt, Bonpland, and Kunth, Bletia grandiflora La Llave and Lexarza, Laelia grandiflora (La Llave and Lexarza) Lindley, Laelia grandiflora var. alba Dimmock, Cattleya grahamii Lindley, Laelia majalis Lindley, Cattleya majalis (Lindley) Beer, Laelia majalis alba hort. ORIGIN/HABITAT: Mexico. Plants are found over a wide area of the central plateau and surrounding highlands in the states of Durango, Zacatecas, Aguascalientes, Jalisco, Guanajuato, Michoacán, Querétaro, Hidalgo, San Luis Potosí, and Tamaulipas. They grow on oak trees in open, dry, deciduous, stunted forests at 6250-8200 ft. (1900-2500 m). The habitat experiences severe drought from Dec.-Jun. (Jun.-Dec.). CLIMATE: Station #76577, Guanajuato, Mexico, Lat. 21.0N, Long. 101.3W, at 6726 ft. (2050 m). Temperatures are calculated for an elevation of 8000 ft. (2440 m). Record extreme temperatures are not available for this location, but records from nearby locations indicate that at this elevation the record high is probably warmer than 100F (38C), and the record low is probably colder than 20F (-7C). N/HEMISPHERE JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC F AVG MAX 67 70 75 80 82 80 76 76 75 74 71 68 F AVG MIN 37 42 45 50 53 55 54 53 53 49 44 42 DIURNAL RANGE 30 28 30 30 29 25 22 23 22 25 27 26 RAIN/INCHES 0.1 0.2 0.2 0.4 1.0 1.7 4.7 2.5 2.2 0.7 0.4 0.4 HUMIDITY/% N/A BLOOM SEASON * * *** *** * * * DAYS CLR N/A RAIN/MM 3 5 5 10 25 43 119 64 56 18 10 10 C AVG MAX 19.4 21.1 23.9 26.7 27.8 26.7 24.4 24.4 23.9 23.3 21.7 20.0 C AVG MIN 2.8 5.4 7.1 9.9 11.6 12.7 12.1 11.6 11.6 9.3 6.6 5.4 DIURNAL RANGE 16.6 15.7 16.8 16.8 16.2 14.0 12.3 12.8 12.3 14.0 15.1 14.6 S/HEMISPHERE JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN Cultural Recommendations: LIGHT: 3000-4000 fc. Bright conditions are required. Light should be filtered or diffused at midday to reduce the risk of sunburn. Strong air movement should be provided at all times. TEMPERATURES: Summer days average 76-80F (24-27C), and nights average 53-55F (12-13C), with a diurnal range of 22-25F (12-14C). These temperatures represent the coolest conditions under which this species should be grown, but the range in habitat elevation, suggests that plants should adapt to conditions 6-8F (3-4C) warmer than indicated. When the growing area is cooled by an evaporative cooler, Laelia speciosa thrives when placed in the strong, cool, moist airflow near the outlet. HUMIDITY: Records are not available for this location, but reports from nearby locations indicate that humidity probably averages close to 65% most of the year, dropping to about 55% at the end of the dry season in late winter and early spring. WATER: Rainfall is light to moderate for 4-5 months from late spring to early autumn. Amounts decrease rapidly in autumn and remain very low during a 7-8 month dry season that lasts until late spring. Cultivated plants should be watered often when they are actively growing, but they must dry quickly after watering. Water should be drastically reduced after new growths mature in autumn. FERTILIZER: 1/4-1/2 recommended strength, applied weekly during periods of active growth. Many growers recommend using a fertilizer lower in nitrogen and higher in phosphorus in late summer and autumn. REST PERIOD: Winter days average 67-70F (19-21C), and nights average 37-42F (3-5C), with a diurnal range of 26-30F (15-17C). Although plants survive short periods of below freezing temperatures in nature, extreme conditions should be avoided in cultivation. Because of the range in habitat elevation, plants should adapt to average temperatures 6-8F (3-4C) warmer than indicated. Rainfall in the habitat is very low from autumn through spring. In autumn, heavy dew frequently provides some additional moisture, but in late winter and early spring, conditions are so dry that even moisture from condensation is rare. Water should be reduced for cultivated plants in autumn. In fact, Laelia speciosa needs to dry out in autumn and remain dry for relatively long periods between waterings. An occasional early-morning misting normally provides adequate moisture in most growing areas. In winter and early spring, however, even misting should be reduced as plants need to stay dry for several weeks at a time. Growers confirm that the dry, cool rest is absolutely essential. Leon Wiard (1987) reported that, "Watering, necessary for good flower production, must be limited to very light, infrequent sprayings from October until new growth starts in spring. My usual recommendation is that light watering be done only on U. S. national holidays during the period, with a choice made between Christmas and New Year's Day." Growers report that new growths and flower buds often blast if the plant is watered too soon. In addition, flower spikes may not even be initiated if too much water is given too soon after new growth starts. Some growers recommend that the frequency of morning mistings should be increased slightly after vegetative growth starts, but that water should not be increased significantly until after flowering. This recommendation appears to be given validity by comparing the monthly rainfall averages with the period of peak blooming. Fertilizer should be eliminated until water is increased in spring. In the habitat, light is brightest during the winter dry season, and cultivated plants need as much winter light as possible. GROWING MEDIA: Growers recommend mounting plants on tree-fern or cork slabs. However, mounted plants need high humidity and at least daily watering in summer, and several waterings a day may be needed during very hot, dry weather. However, plants are most often grown in pots filled with an open, fast-draining medium to allow the roots to dry rapidly after watering. Medium-sized fir bark or cork nuggets work equally well. Plants should be repotted before the medium starts to break down or when the plant overgrows its pot. Plants become reestablished faster if they are repotted just as new root growth is starting, but the brittle new roots must be handled carefully. MISCELLANEOUS NOTES: The bloom season shown in the climate table is based on cultivation records. In nature, plants bloom from late spring to midsummer. Laelia speciosa is considered difficult to cultivate by many growers, so its cultural requirements, especially the need for the exceptionally dry winter, should be given careful attention. Plant and Flower Information: PLANT SIZE AND TYPE: A 7-8 in. (18-20 cm) sympodial epiphyte. PSEUDOBULB: About 2 in. (5 cm) long. Pseudobulbs are pale green to grayish green, egg-shaped, and tightly clustered. They are smooth and covered with papery sheaths when young, but they develop furrows and wrinkles with age. LEAVES: 5-6 in. (13-15 cm) long. A single rigid, leathery leaf is normally carried at the top of each pseudobulb, but some growths may occasionally produce 2. The rather narrow, sharply pointed leaves are often quickly deciduous and may not last until the next growing season. INFLORESCENCE: 5-8 in. (12-20 cm) long. An inflorescence emerges from the center of the new growth in spring, usually before the leaf develops fully. FLOWERS: 1-2. Large, showy blossoms develop rapidly at the top of each inflorescence. The flowers are 4-6 in. (10-15 cm) across with a heavy texture. They are long lasting with a weak fragrance that resembles violets. Pointed sepals and petals are about the same length, but the petals are twice as wide. Sepals and petals are usually pale rosy lilac, but blossoms may be very dark or very pale. The 3-lobed lip, which has rosy lilac borders, is white in the center with short lavender-red lines scattered randomly in the throat and on the midlobe. The red lines on the lip form a unique pattern that is said to be as variable as fingerprints. The lip sidelobes are erect on each side of the column. The almost round, spreading midlobe has wavy margins with a yellow line down the center which is widest at the base. Plants with completely white flowers are found occasionally, but they are rare. Halbinger and Soto (1997) report that plants with the largest flowers and best form originate in Michoacán. HYBRIDIZING NOTES: N/A. REFERENCES: Bechtel, P. 1990. The laelias of Mexico. American Orchid Society Bulletin, 59(12): 1229-1234. Halbinger, F. 1993. laelias de Mexico. Asociación Mexicana de Orquideologia, A. C. México D. F. Mexico. Halbinger, F. and M. Soto. 1997. Laelias of Mexico. Orquidea (Mex) 15(1). Hamilton, R. Orchid nurse. Hamilton, R. 1988. When does it flower? 2nd ed. Robert M. Hamilton, 9211 Beckwith Road, Richmond, B.C., Canada V6X 1V7. Hawkes, A.  1987. Encyclopaedia of cultivated orchids. Faber and Faber, London. Löb, U. 1990. The genus Laelia in Mexico. Schlechteriana 1(1): 8-15. McVaugh, R. 1989 (1986). Orchidaceae, in Flora Novo-Galiciana vol. 16, a descriptive account of the vascular plants of western Mexico. Ed. W. R. Anderson. University of Michigan Press, Ann Arbor, Michigan, U. S. A. Wiard, L. 1987. An introduction to the orchids of Mexico. Comstock Publishing Assoc. Ithaca and London. Withner, C. 1990. The cattleyas and their relatives, vol. II:the laelias. Timber Press, Portland, OR. PHOTOS/DRAWINGS: Bechtel, P. 1990. The laelias of Mexico. American Orchid Society Bulletin, 59(12): 1229-1234. Halbinger, F. 1993. Laelias de Mexico. Asociación Mexicana de Orquideologia, A. C. México D. F. Mexico. Halbinger, F. and M. Soto. 1997. Laelias of Mexico. Orquidea (Mex) 15(1). Löb, U. 1990. The genus Laelia in Mexico. Schlechteriana 1(1): 8-15. Wiard, L. 1987. An introduction to the orchids of Mexico. Comstock Publishing Assoc. Ithaca and London. Withner, C. 1990. The cattleyas and their relatives, vol. II:the laelias. Timber Press, Portland, OR. Copyright 1997, Charles O. Baker and Margaret L. Baker Sheet version 25626147 ......................................................................... 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