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Specific additional cultural information
Philip C. Tomlinson © 1998
For basic cultural information, refer to the Cattleya Culture page. Seasonal cultural
information is also included with that data.
The following page details specific cultural pointers for the genus Laelia,
and should be read with the basic information presented elsewhere.
LAELIA CULTURE
For a discussion of the general cultural requirements for laelias, refer to the discussion on cattleyas.
Those notes indicate the seasonal culture applicable to these plants. The following is intended to supplement those
general notes with specific requirements for the various laelia groups.
The genus laelia is a popular one, both on its own and when hybridised with other
genera in the cattleya alliance. This group of plants is the second most important and desirable group within the
alliance. The number of valid species of laelia are between 50 and 75, depending on whether you are a splitter
or lumper in taxonomic terms.
Laelias have a widespread geographic distribution ranging from Cuba and Mexico, south
to Argentina in South America. The largest number of species is found in 'Brazil. It has been noted that the Mexican
and Brazilian laelias do not breed in the same way, and it is therefore connivent to consider them as two distinct
groups.
Botanists group the individual species into a number of separate sections. As there
as some cultural differences between the plants in the different groups, it is connivent to discuss cultural requirements
on this sectional basis.
The Cattleodes Section, includes the species crsipa, fidelensis, grandis, lobata,
perrinii, purpurata, tenebrosa, virens, and xanthina. Laelia purpurata is probably the finest
plant within this genus, although lobata, crispa and tenebrosa are also most desirable. These plants
can be grown in a similar way to cattleyas, in intermediate to warm conditions. Most experience a degree of seasonality
- warm wet summers and cooler and drier winters. Refer to habitat notes on the Lowland Coastal
Rainforest Habitat and Monsoonal Foothill Habit discussion for more habitat information
and cultural recommendations.
The Hadrolaelia Section includes sincorana, jongheana, the popular and distinctive
pumila, praestans, dayana and alaorii. These species are primarily inhabitants of the savannas
and prairies (see that page for habitat informatin) of Brazil. These are found in the interior of Brazil, where
the influence of the winds from the ocean do not make themselves felt. The altitude usually lies from 500 to 1000
metres above sea level, the topography flat to slightly undulating, with few trees in existence. The isolated islands
of elevated country are characteristic of this region. The orchids found are mainly terrestrial, the epiphytic
orchids (such as the laelias) confined to the narrow stretches of forest and scrub bordering the rivers and lakes
which often extend for hundreds of kilometres. The climate is characterised by hot and dry days and very cool nights.
The oscillation of temperatures from day to night and from summer to winter is significant. Temperatures and humidity
can vary over a considerable range - refer to the discussion on this habitat for detailed
information and specific cultural recommendations.
The Eulaelia Section contains the Mexican species Laelia speciosa. It is a
high elevation plant rarely found below 2000 metres altitude. It is reported to be a difficult plant to culture
successfully because of the difficulty in providing the sunny cool dry conditions it appreciates.
The Microlaelia Section contains two species Laelia cattleyodes and the popular
Laelia lundii. This plant is from the Brazilian prairie habitat, and the notes and
cultural recommendations appropriate for that section should be referred to.
The Parviflorae Section laelias are often referred to with the name 'rupicolous'
referring to their typically rock dwelling habitats. The name 'parviflorae' refers to their typically small flowers,
but the lack of size is m ore than made up by their delightful colours. The main species included in this group
are listed below, together with their habitat reference. . The discussions on these habitats also include specific
cultural recommendations. An excellent article on these orchids is available on the AOS website. Click here
to visit.
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Laelia Alliance Species
Habitat zones
(List as originally published by G.F.S Pabst and F. Dungs in Orchidaceae Braziliensis)
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LAELIA ALLIANCE
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FOOTHILL
MONSOONAL HABITAT
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DRY
SAVANNA/PRAIRIE HABITAT
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Harphphylla
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brevicaulis
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..
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harpophylla
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.
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kautskyi
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.
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Crispata
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caulescens
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crispata
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.
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crispilabia
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mantiqueirae
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.
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longipes
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.
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pfisteri
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Liliputina
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.
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ghillanyi
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..
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lilliputana
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.
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lucasiana
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.
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malletii
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...
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reginae
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Flava
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.
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angereri
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bahiensis TROPICAL HOT LOWLAND RAINFOREST HABITAT
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.
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blumerscheinii
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..
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briegeri
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cinnabarina
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cinnabarina
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.
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acinnamomea
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endsfeldzii
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flava
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gloedeniana
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macrobulbosa
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.
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milleri
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mixta
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..
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Esalqueana
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braderi
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.
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esalqueana
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..
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itambana
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The culture of the species of this section require some special care, and differ in important elements
according the to the unique habitats and environmental adaptations that set them apart form cattleyas and most
other laelias. These laelias come from barren quasi-xerophytic mountain ridges. The species are nearly all rupicolous
- rock dwellers - growing on open rock surfaces, their roots creeping along crevices and fast drying water courses
and are largely exposed to the fresh air. Their pseudobulbs and leaves show the characteristics of other xerophytic (air) plants - succulent or leathery foliage geared to conserve water. The degree of
succulence varies between those with short stout thick leaved species that live in full exposure to the sun, and
those taller leathery blade leaved species sheltering in the partial shade of small shrubs, the elongated inflorescence
reaching above the foliage of the surrounding vegetation. These degrees of plant habit provide excellent clues
to an observant grower as to the cultural needs of each species - the amount of light, potting medium, drainage,
and temperature ranges.
Certain non-rupicolous typically epiphytic species such as Laelia harpophylla who no succulence
or thickening, and take the usual cattleya conditions as set out elsewhere.
Culturally, with respect to the Parviflorae species, the thicker the leaves, the more light
is required for good growth. They require intermediate temperatures during the day with a
maximum of 27 to 35 degrees Celsius. The lower end of the range is satisfactory if sufficient light is provided.
Night time temperatures shooed range from 11 to 13 degrees Celsius in winter, cooler than what may be given many
cattleyas in our glasshouses. When these plants are reluctant to flower, lower temperatures may assist in flower
bud initiation.
The correct potting and mounting of these plants is perhaps the most critical element
for the culture of these species. plants naturally grow exposed to the air, warned by the head radiating from the
sun soaked rock. Rain and morning dew dries quickly. The moisture the plants need is trapped in the spongy, insulated
roots and the fleshy leaves. These conditions must be simulated in cultivation. The medium
should be open, airy, fast draining and drying. Cattleya mixes based on bark are often too wet or compacted for
adequate drying at the roots. Logically, a medium based rock or gravel may be considered. Granite, lava or some
other rock could be suitable if not too acid or alkaline as it can be from some sources. Hardwood charcoal is good,
although some gravel may be used to hold its lightness down. Tree fern fibre arranged vertically has worked well
in clay pots for some growers. The best medium for your conditions will have to be experimented with, as will the
issue of clay or plastic pots. Repot during active root growth. Mounting on cork or tree
fern slabs can work if the slabs are large enough to accommodate a good many roots. The plant should sit vertically
on the horizontally hung slabs, as though sitting upright in its natural position on a rock surface.
Allow the roots to dry out between waterings. Cool moist conditions
make for longer periods between watering. Humidity should be high at all times to prevent desiccation, especially
for slab mounted plants. Daily misting of the tops of the plants during warm and dry weather is beneficial.
The plants are subjected naturally to a rather prolonged spell of rainlesness in the autumn
and winter. The spell begins after the plants have flowered, and may last for 5 months. They rest during
this period, existing on natural humidity and morning dewfall, until the new growth resumes with the early spring
rains. Cut back watering completely after flowering, just mist occasionally to keep the leaves and pseudobulbs
plump. Resume watering only when new growth appears in the spring.
The key to the culture of these plants is tied to their need for high light levels,
cool nights, high humidity, and a fast drying airy medium for their dry loving roots.
The Podalaelia Section comprises the Mexican laelias, such as anceps, albida,
autumnalis, and rubescens. Many of these species come from the Monsoonal Foothill
Rainforest habitat, which is subject to the summer monsoon, warm humid summers when the main growth occurs,
and cool dry winters when they rest. A number come from the higher altitudes, and are therefore cooler growing
.- species such as anceps, albida, autumnalis.
Culturally they come from the foothill mountain habitat, and that information can
be usefully referred to. Different species require cool to intermediate conditions. They are equipped with quite
heavy leathery leaves, confirming that they can stand quite dry conditions. It can be noted that over-watering
i.e. watering too frequently, especially during the winter months, is the main cause of their death in our glasshouses.
The final laelia Section Calolaelia contains plants now generally listed separately
as schomburgkia.
Photographic slide show
Photographic
slide show = cattleya alliance
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