Trichocentrum (Oncidium) Ollie Palmer

Trichocentrum (Oncidium) Ollie Palmer is a secondary hybrid registered by R.H. Palmer with the Royal Horticultural Society in 2009, derived from Trichocentrum Maureen and Trichocentrum x haematochilum. Its parentage combines Trichocentrum lanceanum (50%), T. carthaginense (25%), and T. luridum (25%). The plant is medium-sized, can reach approximately 50 cm, and has almost no pseudobulbs or very small pseudobulbs. The leaves are solitary, leathery, oblong-lanceolate, green, up to 50 cm long and 12.5 cm wide. The flowers are fragrant.

It can bloom several times a year. Long flower spikes of up to 45 cm generally bear 10–12 waxy, long-lasting flowers, measuring 5–6 cm. The petals and sepals are white marbled with violet, with an irregular border; the lip is a more uniform violet, with a wider white band, while the column is white. Do not cut off healthy leaves after flowering: in this hybrid, reserves are stored in the leaves and roots rather than in large pseudobulbs.

Medium to bright, filtered light is suitable. An east-, west-, or protected south-facing window works well, with ventilation. Leaves that develop a reddish tint indicate that the light is too strong and should be reduced slightly. Warm temperatures are preferred, approximately 20–33°C, with milder nights. The plant can also tolerate lower temperatures for short periods, but dry heat and stagnant air cause stress.

Water thoroughly during the growing period when the substrate is approaching dryness, then allow the water to drain completely. Do not leave the roots standing in stagnant water. In dry indoor conditions, higher humidity is helpful, but it does not replace proper watering. During active growth, fertilize with a diluted solution after watering, using orchid fertilizer.

It can be grown mounted on a piece of bark if humidity is high and watering is frequent during summer. In a pot, choose a coarse, airy mix made from larger-grade bark, optionally with a little sphagnum, that retains moisture without becoming compacted. An airy orchid substrate is a good starting point if you adapt it to the volume of the roots. Repot when the substrate breaks down or new roots appear; the roots do not tolerate old, decomposed mix well.

If the plant does not bloom, first check the light, temperature, and condition of the roots. Soft or wrinkled leaves may indicate prolonged thirst or damaged roots. Scorch marks appear after excessively strong direct sunlight, especially following a sudden move from shade.