The Orchidaceae (orchid family) is one of the largest families of flowering plants. It is, also, one of the most diverse and widespread families, with 763 genera and about 28,000 species from lowland tropics, to mountain cloud forests, to temperate meadows, to arctic tundra. Breeders have produced more than 100,000 hybrids and cultivars. The choices for your orchid collecting passion are nearly endless!
When learning how to grow a particular genus or even a specific species of orchid, it is good to start with learning about its native environment. What is the seasonal and diurnal temperature? What is the light intensity and duration? What is the humidity? Most orchids will tolerate humidity around 50%; however, those from the cloud forests will need humidity in excess of 75%. What is the seasonal rainfall? Are they from a monsoon climate, where summers are very wet and winters are very dry? Most orchids are epiphytes, growing on tree branches and tree trunks; some are lithophytes, growing on rock; and others are terrestrial. Air is as important as water to the health of an orchid’s roots!
Knowing the answers to these questions will guide you in providing the optimal culture for the orchids you want to grow. Don’t be intimidated! Thankfully, orchids can be arranged into cultural groups, where they benefit from similar culture.
Temperature Groups
| Night | Day | |
| Cool (C) | 50–55°F | 60–68°F |
| Intermediate (I) | 55–60°F | 73–80°F |
| Warm (W) | 65–70°F | 80–85°F |
| Hot (H) | >70°F | >85°F |
Light Groups
| Foot-candles | kLux | |
| Very High (VH) | 6000–8000 | 64–86 |
| Bright (B) | 5000–6000 | 54–64 |
| Bright Diffuse (BD) | 4000–5000 | 43–54 |
| Light Shade (LS) | 2000–3000 | 21–32 |
| Medium Shade (MS) | 1000–1800 | 10–19 |
Watering Groups
| Daily Watering (DW) |
| Evenly Moist between Waterings (EM) |
| Barely Moist between Waterings (BM) |
| Dry between Waterings (D) |
| Drier Months during Winter (DM) |
| Dry Winter Rest (DWR) |
Below are examples from some of the more commonly grown genera of orchids with notes about their nativity and basic culture.
Genus: Angraecum (Comet Orchid)
Nativity: Lowland tropics of Africa and Madagascar
Temperature Group: Warm to hot
Light Group: Bright diffuse
Humidity: 65–80%
Watering Group: Evenly moist during active growth; dry between waterings at other times; some drier during winter
Genus: Anguloa (Tulip Orchid)
Nativity: Upland and montane tropics of South America
Temperature Group: Intermediate to cool
Light Group: Light shade
Humidity: 50–80%
Watering Group: Evenly moist during active growth; drier during winter
Genus: Cattleya and Laeliinae relatives
Nativity: Lowland tropics of Central and South America
Temperature Group: Intermediate
Light Group: Light shade to bright diffuse
Humidity: 65–80%
Watering Group: Dry between waterings
Genus: Cymbidium (Boat Orchid)
Nativity: Upland and montane tropics and subtropics of Asia to Australia
Temperature Group: Intermediate to cool
Light Group: Very high
Humidity: 50–80%
Watering Group: Barely moist between waterings
Genus: Dendrobium
Nativity: Lowland tropics of south, east, and southeast Asia; New Guinea; Australia; Vietnam; and Pacific islands
Temperature Group: Intermediate to warm
Light Group: Light shade
Humidity: 50–60%
Watering Group: Evenly moist during active growth; dry between waterings at other times; some need dry winter rest during dormancy
Genus: Dracula (Monkey-faced Orchid)
Nativity: High-elevation montane tropics of Central and South America to Mexico
Temperature Group: Cool
Light Group: Medium shade
Humidity: 75–85% with morning “cloud forest” of 95–100%
Watering Group: Evenly moist to daily watering
Genus: ×Gastrophaius (Nun’s Orchid)
Nativity: Nothogenus hybrid between Gastrorchis and Phaius
Temperature Group: Intermediate to warm
Light Group: Light shade
Humidity: 65–80%
Watering Group: Evenly moist during the growing season and drier during winter.
Genus: Lycaste
Nativity: Upland tropics of Central and South America and Mexico
Temperature Group: Intermediate
Light Group: Bright diffuse
Humidity: 50–80%
Watering Group: Barely moist between waterings; drier during winter
Genus: Masdevallia
Nativity: High-elevation montane tropics of Central and South America and Mexico
Temperature Group: Cool
Light Group: Medium shade
Humidity: 75–85% with morning “cloud forest” of 95–100%
Watering Group: Evenly moist to daily watering
Genus: Miltoniopsis (Pansy Orchid)
Nativity: Upland Tropics of Central and South America
Temperature Group: Cool to intermediate
Light Group: Medium shade
Humidity: 50–80%
Watering Group: Barely moist between waterings
Genus: Oncidium (Dancing Lady Orchid)
Nativity: Lowland tropics of Central and South America, Mexico, and West Indies
Temperature Group: Intermediate to warm
Light Group: Light shade
Humidity: 50–80%
Watering Group: Barely moist between waterings
Genus: Paphiopedilum (Lady’s Slipper Orchid)
Nativity: Lowland tropics of southeast Asia, southern China, India, New Guinea, and Pacific islands
Temperature Group: Intermediate to warm for mottle-leaved and multiflora plants; cool for green-leaved plants
Light Group: Light shade to bright diffuse for multiflora plants; medium to light shade for all others
Humidity: 50–70%
Watering Group: Barely moist between waterings
Genus: Phalaenopsis (Moth Orchid)
Nativity: Lowland tropics of south, east, and southeast Asia; New Guinea; and Australia
Temperature Group: Warm
Light Group: Medium shade
Humidity: 50–70%
Watering Group: Barely moist between waterings
Genus: Phragmipedium (Lady’s Slipper Orchid)
Nativity: Upland tropics of Central and South America
Temperature Group: Intermediate to warm
Light Group: Light shade
Humidity: 50–80%
Watering Group: Evenly moist to daily watering
Genus: Vanda
Nativity: Lowland tropics of east and southeast Asia, New Guinea, and Pacific islands
Temperature Group: Warm
Light Group: High to full sun
Humidity: 65–80%
Watering Group: Daily watering
Genus: Vanilla
Yes, the flavoring comes from the dried fruit (seed capsule) of the Vanilla planifolia orchid!
Nativity: Lowland tropics of the Caribbean, Central and South America, and Mexico
Temperature Group: Warm to hot
Light Group: Medium shade
Humidity: 50–70%
Watering Group: Barely moist between waterings