Cymbidium Alexanderi gx
boat orchid Alexanderi gx
A large-sized, evergreen orchid with linear, dark green leaves up to 90cm long and 2cm wide. Ovoid pseudobulbs covered with basal leaf sheaths carry six to ten leaves. The orchid flowers in early spring on upright or arching stems up to 100cm tall, carrying up to 30 flowers. The flowers are white, pale pink or cream, depending on cultivar, each measuring 7-9cm across. Perhaps the most famous cultivar 'Westonbirt' with large pure white flowers and with pink markings on the lip was originally registered in 1911. It is the first orchid hybrid which was identified a tetraploid - carrying four (instead of two) sets of chromosomes, which set a start to a very successfull history of breeding.
Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Well–drainedpH
NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | White Pink | Green | ||
|---|---|---|---|---|
| Summer | Green | |||
| Autumn | Green | |||
| Winter | White Pink | Green |
Position
- Partial shade
Aspect
East–facing or West–facing
Exposure
Sheltered Hardiness
H1CBotanical details
- Family
- Orchidaceae
- Native to the UK
- No
- Foliage
- Evergreen
- Habit
- Clump forming
- Potentially harmful
- Skin allergen. Wear gloves and other protective equipment when handling
- Genus
Cymbidium are epiphytic, lithophytic or terrestrial orchids with prominent spherical to ovoid pseudobulbs, long linear leaves and fleshy white roots. Several long lasting showy flowers with a distinctive 3-lobed lip are borne on erect or arching flower spikes from the bases of the pseudobulbs
- Name status
Accepted
How to grow
Cultivation
Grow in an open, free-draining orchid compost with addition of perlite, sphagnum moss or coir. Requires day temperatures around 16°C and 10°C at night. Provide good light levels, but avoid direct sunlight. Water plants thoroughly when compost is almost dry, allow to drain and use orchid fertiliser regularly during growing season. Reduce watering in winter. Place outside in dappled shade during the summer months to aid flower initiation. See cymbidium cultivation for more detailed information.
Propagation
Propagation by seed is only possible in a controlled laboratory environment. Mature plants may be divided in early or mid spring, when the plant overgrows its container. Each division should have at least 3 older pseudobulbs with a sufficient amount of stored energy and water, to support new growth and reduce stress after repotting.
Suggested planting locations and garden types
- Houseplants
- Patio and container plants
- Conservatory and greenhouse
- Cut flowers
Pruning
No pruning required. Cut down flowered stems to base.
Pests
May be susceptible to aphids, glasshouse red spider mite, scale insects and mealybugs
Diseases
Generally disease-free. Sterilising cutting tools may prevent virus diseases, such as Cymbidium Mosaic Virus (CMV).
Get involved
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