Oncidium excavatum is a robust species with long lasting flowers and is always a star of our Autumn greenhouse. Oncidium excavatum is a terrestrial species found in Peru and Ecuador where it grows on steep banks from 2400 to 2800m altitude in cool forest. Like many of the terrestrial oncidiums it has long upright flower spikes to present the flowers above surrounding vegetation and the flowers are clustered near the top of the branched spikes. This gives a flowering plant great impact.
We have grown the species in pots and baskets in both our cool Americas and warm americas sections and conclude that for us it grows best in Warm Americas (minimum 15C) in good light and in baskets with plants watered throughout the year but with great drainage. Flowering reliably happens in the autumn and the long lasting flowers will still be with us at Christmas.