A little Introduction
The sweetly scented Brassavola nodosa (L.) Lindl. more commonly known as Lady of the Night orchid, belongs to the rather extensive Orchidaceae family, and is part of the Brassavola genus, which contains approximately 21 species. The majority of the Brassavola species grow on trees (epiphytic) with a few exceptions where they prefer growing lower down on rocks (lithophytic), (Schemske, 1980).
The species Brassavola nodosa is typically recognised by its very strong nocturnal fragrance but, compared with other orchid species such as those in the Cattleya genus, is a relatively small orchid. When found growing in its natural habitat it will usually grow in clumps, spanning between 40-50cm. This is when multiple shoots are produced which then forms a clump. However, more often there is only a single shoot produced with a single leaf. This growth habit is referred to as symbiodal growth (Murren & Ellison 1996).
The specimens we are growing in the campus tropical greenhouse are young and not near flowering. In the wild B. nodosa usually flowers for long periods, from 3 months to the best part of the year (Murren & Ellison 1996). However, the duration of flowering is highly dependent on the geographic location as B.nodosa, for instance, when growing in the Panama region (Figure 4) and flowers from August November (Schemske, 1980).
The B.nodosa inflorescence produces 1-7 flower clusters at a time, known as a raceme. The colour ranges from ivory to pale green (Murren & Ellison 1996). In many of the hybrids the flowers have distinct coloured spots on the lip (American Orchid Society, 2012). The flowers themselves consist of 5 thin tepals with a wide lip which can measure up to 7cm wide. Although the flowers are considered to be potentially self-fertile, they still require pollination at night by moth species (Schemske, 1990). According to some studies, the larger flower size optimizes male flower reproduction as the pollinator seem to visit the larger flower more frequently than the smaller flowers (Tremblay 2003). However, the plant in our greenhouse is looking healthy with lots of new growth, the longest shoot was measured at 17.2cm in length (Fig 4). The leaves are tough and waxy to the touch with a prominent midrib running down the centre of the leaf (primary vien). As shown in Figure 3, B.nodosa has thin psuedobulbs often these are covered by a thin transparent sheathing which allows the orchid it to cope in dry habitats or during periods where water is limited .
How does it differ from other species within the Brassavola Genus?
In 1813 the Brassavola genus was created by Scottish Physician Robert Brown, within this genus there have been quite a few species revisions and name changes. Originally Carl von Linné described Brassavola nodosa as Epidendrum nodosum L. (The Plant List, 2010). Since then it has had many synonyms associated with the species such as Cymbidium nodosum and Bletia nodosa, and to finally reach the now widely accepted Brassavola nodosa. It is the most know species within the genus and within the Cattleya Alliance due to its diverse distribution demonstrated in the species map below (Figure 6). This is a representation from the Global Biodiversity Information Facility (GBIF) mapping real data. In the past the Brassavola genus was actually considered to be part of the Rhycholadia genus forming one, as both are pollinated by Sphingid moths (Jones, 1969). However, after further DNA analysis the two groups were separated due to their distinct flower structure.
Within all plant genera there is what is known as a nomenclature type. This is fixed species associated to the genus name (International Code of Nomenclature for algae, fungi, and plants, 2012) . For this genus the type species is Brassavola cucullata known for its spectacular drooping white flowers (American Orchid Society, 2012). Just like B. nodosa it has a strong nocturnal fragrance and a wide growing distribution. B.cucullata has a similar symbodial growth habit but its leaves are much narrower than B.nodosa (American Orchid Society, 2012).
Cultivation for Brassavola nodosa, what does it need to grow?
Though this is not an edible plant, it is highly regarded in the ornamental sector and is thought to be a relatively easy orchid to grow. The reward for growing and caring for Brassavola nodosa is the beautiful scent which fills the air once the evening starts. For the optimum results it is best to grow this orchid mounted on tree bark or in a basket, this will allow the aerial roots to grow freely (The Atlanta Orchid Society Bulletin, 2010). In its natural habitat B.nodosa will experience a wet rainy season followed by a dry one in good light conditions. It is best to follow this pattern for optimal results while watering frequently is needed. It is key to ensure free drainage, and maximum humidity is also advisable as B. nodosa can withstand up to 80% humidity in its natural habitat. In case baskets or bark is not an option, one can pot up this orchid in a light bark mix making sure some of the aerial roots are on the surface and free drainage is provided (The Atlanta Orchid Society Bulletin, 2010). With regards to temperature, it is best to maintain a temperature above 12°C to ensure the orchid will produce flowers. In order to really maximise the flower production a temperature range of 18-27°C is advised.
Where does the Lady of the Night grow?
B. nodosa is native to Mexico, central and northern South America. Its distribution is quite widespread as you can see from Figure 6 it grows in most regions from North Mexico stretching to South America, with a few occurrences in the West Indes.
In some regions B.nodosa has been found to naturally hosted on different trees within its region of distribution. The species is found on mangroves including the buttonwood mangrove, Conocarpus erectus L. in Belize, to the red mangrove, Rhizophora mangle (Murren & Ellison 1996), which seems to be a favourite host tree for B.nodosa, thriving on tree branches and the lower trunks. Brassavola nodosa can also be found growing on the exposed rocks and cliffs of the Costa Rica coast (Murren & Ellison 1996).
It seems for our B.nodosa there are only two common names by which it is referred to by: Lady of the Night or the spanish equivelent Dame de la Noche.
America Orchid Society (2012) Collector’s Item:Brassavola cucullata (L.) R.Br http://www.aos.org/Default.aspx?id=153 (accessed on 25th November 2012).
eMonocot (2012) version 00.21. Brassavola nodosa (L.) Lindl. Gen. Sp. Orchid. Pl. : 114 (1830) http://zoo-bclark01.zoo.ox.ac.uk/taxon/urn:kew.org:wcs:taxon:24179 (accessed on the 14th November 2012)
International Code of Nomenclature for algae, fungi, and plants (2012) Chapter II. Status, Typification, and Priority of Names, Article 7.2<http://www.bgbm.org/iapt/nomenclature/code/saintlouis/0011Ch2Sec2a007.htm> accessed 12th December 2012.
Jones. G. H. (1969) Studies in Brassavola. I. Phyton (Austria). 14, 31-35
Murren, C. J. & Ellison, A. M. (1996). Effects of Habitat, Plant Size and Floral Display on Male and Female Reproductive Success of the Neotropical Orchid Brassavola nodosa. Biotropica. 28, 30–41.
Schemske, D. (1980). Evolution of floral display in the orchid Brassavola nodosa. Evolution. 34, 489–493.
The Atlanta Orchid Society Bulletin. (2010) Integrated Orchid Conservation at the Atlanta Botanical Garden. The Atlanta Orchid Society Newsletter. 51(8)
The Plant List (2010). Version 1. Published on the internet www.theplantlist.org/ (accessed 2oth October 2012)
Tremblay, R.L., Ackerman, J.D., Zimmerman, J.K. & Calvo, R.N. (2003). Variation in sexual reproduction in orchids and its evolutionary consequences: a spasmodic journey to diversification. Biological Journal of the Linnean Society, 84, 1–54.
Withner, Carl. 1992. The Cattleyas and their Relatives, Volume V. Timber Press. Portland I. McLeish, N.R.Pearce & B.R.Adams. 1995. Native Orchids of Belize. A.A.Balkema. Rotterdam