Tolumnia (Mix Colour)

Mix-color Tolumnia orchids—often grouped within the Oncidium alliance—combine the charm of vibrant, variegated blooms with the easy-going nature of many Tolumnias. Their care is similar to that of other Tolumnias, but here are some tailored tips:

Light

• Bright, Indirect Sunlight:
Provide at least 2000–3000 foot-candles of bright, diffused light (such as from an east or west window). While they can tolerate some direct morning or evening sun, harsh midday rays should be filtered to protect the delicate leaves.

Temperature & Humidity

• Moderate Temperature Range:
Aim for daytime temperatures around 70–80°F (21–27°C) and slightly cooler nights near 60–65°F (16–18°C).
• Good Humidity & Airflow:
Maintain a humidity level of about 50–70% and ensure plenty of air circulation. This mimics their natural epiphytic habitat and helps the roots dry quickly after watering.

Watering

• Wet/Dry Cycle:
Water thoroughly when the growing medium is nearly dry. These orchids benefit from a quick soak followed by a period of drying—just as they would naturally on a tree branch in the Caribbean.
• Water Quality:
Use lukewarm, low-alkalinity water (rainwater, distilled, or reverse osmosis water) to prevent salt buildup and root damage.

Potting & Media

• Well-Draining Mix:
Use an airy mix such as coarse orchid bark combined with a bit of sphagnum moss and charcoal. This mix supports the fast-drying, “breathable” environment that Tolumnias prefer.

• Balanced Feeding:
During the active growing season, feed with a diluted, balanced orchid fertilizer (or one with slightly higher nitrogen) with each watering or every other watering. Reduce feeding during the resting phase to prevent salt buildup in the media.