Cymbidium Orchid - Features and Care Guide

The genus Cymbidium includes 52 botanical species, with persistent leaves, belonging to the Orchidaceae family. The genus name comes from the Latin word for boat (cymba).

From a morpho-physiological point of view, species of the genus Cymbidium are herbaceous, perennial, but form annual branches. There are known species that occupy corticolous habitats (on tree bark), in hollows, in humus, or terrestrial species (growing on soil). Generally, new root growth appears on young plants, with development for old bulbs being a rarer event. The stem of Cymbidium species is short and connects the pseudobulbs, which are actually thickened branches of the stem. When old pseudobulbs are separated from the main specimen, the phenomenon of developing new branching growths may occur, thus regenerating a new plant. Due to the multidirectional growth of the stem (a pseudorhizome, in this case), species of the genus Cymbidium are considered sympodial (as opposed to monopodial, unidirectional growth, as in species of the genera Vanda and Phalaenopsis, among the best known).

Pseudobulbs are often spherical or ovoid in shape, with a diameter ranging from 1 cm to 15 cm, frequently covered by the basal area of the leaves. The leaf appearance can be divided into two forms: scaly, when attached to a segment of the rhizome, and true leaves, when inserted on the pseudobulb. Normally, the leaves have a petiole, which is less distinguishable by shape but clearly structural, through the presence of a demarcation zone. After leaf fall, the petioles remain attached to the pseudobulbs. The petiole is not present in all species.

Depending on the species, the leaf shape can show significant differences, with a prominent or immersed central vein in the leaf surface. The leaf color varies from yellowish green to dark green, and the abundance of foliage and leaf thickness are also subject to considerable variability. In species that inhabit regions with strong light intensity, the leaves have a reduced width but greater thickness compared to species that prefer more shaded areas. The leaf tip is usually acute, the width ranges between 0.5 and 6 cm, and the leaf length is generally within the range of 10 – 150 cm.

The flower stalks emerge from the base of the pseudobulbs. Usually, each pseudobulb blooms only once during its lifetime.

The genus Cymbidium was identified in nature by orchid hunters around the beginning of the 19th century, in Asian jungles, the collected specimens later being transported and planted in Europe. These initial wild varieties represented the genetic material on which most of the crosses later present in commerce were produced. The purpose of these hybridizations was to create varieties with high economic and aesthetic value, with abundant flowering, large, durable flowers, and exceptional coloration. For this reason, European cymbidium hybrids have exceptional sizes compared to specimens grown in the rest of the world.

The first Cymbidium hybrid appeared in 1889 - Cymbidium eburne x lowianum. In the next 20 years, only 14 new species were discovered, but they did not present horticultural interest. However, later, in the first decade of the 20th century, numerous other species were discovered in Burma and Indochina, especially in Cambodia. Species such as parishii, insigne, and erythrostylum thus played an important role in creating spectacular new hybrids. Species like hookerianum and lowianum were the basis for producing hybrids with green flowers, eburneum and insigne created hybrids of white and pink color, traceyanum generated yellow varieties, ansonii, red and pink flowers, and parishii gave rise to specimens with red labellum, such as Cymbidium Miretta.

H.G. Alexander, a famous Cymbidium breeder, produced at the beginning of the current century the hybrid Cym. Alexanderi Westonbirt (eburneolowianum x insigne), a taxon of invaluable value for the subsequent creation of new varieties of hybrids with white, pink, yellow, green flowers, especially blooming in autumn and during winter. Cymbidium Pauwelsii (insigne x lowianum) was the first cross to produce large flowers, like Cymbidium Babylon (Olympus x Pauwelsii), which in turn was used to create new varieties featuring vibrant colors.

In terms of size, species of the genus Cymbidium are divided into two groups: standard and miniature, although recently crosses between the two types have been made. Taxa with pendulous inflorescences were created using species such as devonianum and aloifolium.

Optimal growth temperature for species of the genus Cymbidium involves a significant difference between daytime and nighttime temperatures. The daytime temperature should be within the range of 27 – 32 ℃, and the nighttime temperature between 10 – 15 ℃. As a basic rule, it is necessary to provide a temperature difference of 13 – 16 ℃, at least during some periods of the year, to ensure successful flowering.

Ideally, in the cold season, Cymbidium will be placed in very bright rooms with temperatures of 10-18 degrees. Plants can also be grown outdoors, as long as temperatures do not drop below 3-10 degrees (depending on species/hybrid) and adequate humidity conditions can be ensured.

The ideal temperature during the flowering period will also be in the range of 10-18 degrees, the persistence of the flowers being directly influenced:

10-12 ℃ - flowers last approx. 12 weeks
21 ℃ - flowers last a maximum of 3 weeks

Cymbidium orchids in production greenhouses

Species of the Cymbidium genus require abundant lighting, but the light should be partially filtered to prevent sunburn on the leaves. Strong lighting will facilitate flowering, which will be more abundant and with more intense colors, while lack of it will produce flowers with pale colors. Although with adequate lighting, Cymbidium orchids do not require fertilization, periodic application of a fertilizer will lead to more abundant flowering.

The required humidity for most Cymbidium species should be within the range of 40 – 70%, depending on the requirements of each species. Also, in the warm season, spraying with water is recommended during the morning or afternoon to increase humidity.

Watering of orchids from the Cymbidium genus is usually done once a week, but in the warm season the recommended frequency is once every 2 – 3 days, depending on local climatic parameters (relative atmospheric humidity, lighting, temperature, ventilation). Abundant watering is recommended during the growing season (avoiding prolonged water stagnation), but it will be reduced once the development of new growths is completed, without allowing the substrate to dry out completely.

Fertilization of Cymbidium species will be done with a 30 – 10 – 10 formula during the growing season, at no more than 25% of the concentration recommended by the manufacturer on the packaging. At the end of August and the beginning of September, a fertilizer of type 6 – 30 – 30 or 10 – 52 – 10 will be used until the end of November, when fertilization will be completely stopped, administering only water. Applying fertilizer after November can lead to flower abortion or the development of deformities.

Changing the substrate for Cymbidium species should be done every 2 – 3 years, or even 4 – 5 years if the specimens are planted in coconut fiber substrate. If the plant no longer fits in the pot or root system problems are observed, the plant can be moved.

Before replanting and/or dividing the plants, the substrate should be left to hydrate for a few hours in water. Under no circumstances should universal humic substrate or peat be used, as these will cause rapid root rot. After the flowers wilt, they should be removed, as their falling and decomposition in the growing medium will weaken the plants. Similarly, towards the end of flowering, when only 2 – 3 flowers remain on the flower stem, it is recommended to cut and remove it to avoid wasting the energy resources of the pseudobulbs, which will significantly negatively affect flowering in the next season. The end of flowering is the most suitable time for division or changing the substrate/container, as well as for cleaning roots showing signs of fungal or bacterial diseases. When dividing, it is recommended to keep groups of 3 – 5 pseudobulbs, which should be carefully washed, left to dry, and then stored in tied plastic bags in cool places. When choosing growing containers, tall pots that can provide proper stability for the plant and enough space for growth for at least 2 – 3 years are recommended. Old pseudobulbs should be placed near the edge of the container to allow new growth to develop in the opposite direction.

The complete Cymbidium offer from Secret Garden is available here (link).