Brassia lawrenceana

RHS Plant Profile
spider orchid

Synonyms

Brassia cochleata
Brassia angusta

Conservatory Greenhouse Houseplants

A medium to large-sized epiphytic orchid, with elliptic, dark green leaves up to 40cm long. Pseudobulbs are oval shaped, partially covered with green, leafed sheaths. In spring, produces 40cm long, arching flowering stem, carrying 7-11 flowers. Each flower is approximately 5cm large, with thin and slender petals and sepals. Flowers are yellow or green, with red-purple spots. The distinct shape of flowers has evolved to mimic spiders to attract wasp species conducive to successful pollination.

Position

Partial shade

Max Height

0.1-0.5 metres

Max Spread

0.5-1 metres

Size

Time to Maturity
5–10 years
Max Spread
0.5-1 metres
Max Height
0.1-0.5 metres

Growing Conditions

Moisture
Well–drained
pH
Neutral

Position

Partial shade
Aspect
East–facing or North–facing or West–facing
Exposure
Sheltered
Hardiness
H1B

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Orchidaceae
Native to GB/Ireland
No
Foliage
Evergreen
Habit
Clump forming
Genus
Brassia are small to very large epiphytic orchids with ovoid to cylindrical pseudobulbs, each bearing 1-3 strap-shaped leaves and often showy flowers in racemes of up to 12 spider-like fragrant flowers from the bases of the pseudobulbs
Name Status
Correct
Plant Range
N & E S America

How to Grow

Cultivation

Grow in an open bark-based orchid compost with addition of perlite, sphagnum moss or coir. Provide enough bright filtered light, but keep away from direct sunlight or a heating source. Ideal temperatures are around 15°C minimum at night and up to maximum 25 °C during day. Water regularly, when the pot feels light when lifted. Ensure that all water drains away, preventing the plant sitting wet. Orchid fertiliser can be applied regularly throughout the growing season. Reduce watering and feeding in winter months. The orchid will naturally produce aerial roots, growing outside of the pot. As with many orchids, they grow best when well-established and slightly pot-bound. Re-potting should be only done if the plant overgrows its container or before the potting mix starts to deteriorate - approximately once in 2-3 years.

Propagation

Mature plants may be divided 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
  • Conservatory and greenhouse

Pruning

No pruning required

Pests

May be susceptible to mealybugs, aphids and scale insects.

Diseases

Generally disease-free.