Lady of the Night is the common name of Brassavola nodosa, an epiphytic orchid native to low-lying coastal regions of Central and Southern America. It is widespread from Mexico to Colombia and throughout the Caribbean coast and islands, and ranges into Brazil, Bolivia and Peru. It is generally found in lowland tropical forests or mangrove swamps, growing on trees or on exposed rocks and cliffs near the shore. The white to pale green flowers are usually about 3½ inches in diameter (but some may be up to 6 inches), and wonderfully fragrant in the evening. Each flower has long, slender sepals and petals, and a large, heart-shaped lip on the tubular lower petal. The lip may have purple or dark red spotting inside the tube.
B. nodosa is a very easy orchid to grow, adapting to a wide range of conditions in cultivation. A large specimen plant may have dozens of flowers, making quite a display but even a single flower spike is quite rewarding. It likes the same conditions cattleya and laelia orchids do, so if you can grow them successfully, this is a species to consider growing. Provide the plant with good light and intermediate temperatures (65º to 80ºF during the day with a 10ºF drop at night) for best flowering. It may not flower, however, if kept at temperatures below about 55ºF. Water regularly, allowing the potting medium to dry slightly between waterings. Keep plants on the dry side when temperatures are cool. Allow at least a 2 week dry period in the winter when the plant is not actively growing to help mature growths and induce flowering.
Plant in medium to large orchid bark mix in a pot just large enough to hold the roots. If you can provide high enough humidity (tough in the winter in most centrally-heated homes), these plants can also be mounted on slabs of cork or tree-fern fiber. Plants grown on a slab need to be watered at least once daily during the summer.
New leaves are produced from short rhizomes off of older leaves. Established plants tend to start several new growths, so large clumps develop readily. A single fleshy, almost cylindrical leaf with a groove on the upper surface is produced from each growth. Leaf length varies considerably depending on light, water and temperature conditions. A single flower spike arises from each leaf axil as the new growth matures, bearing 1-6 flowers. The lovely flowers last several weeks (longer in cooler conditions). Unlike most orchids that only bloom annually, B. nodosa often blooms more than once a year. Flowers may occur at any time of year, but most often in autumn or winter.
– Susan Mahr, University of Wisconsin – Madison