Oncidium Fire Cracker   This is a truly miniature orchid that blooms reliably under lights.  It is very loosely potted in sphagnum moss in a 2.5 inch clay pot.   Leaves that are 4 to 5 inches (10 to 12.5 cm) long are arranged like a fan.  However, the flower spike is about a foot (30 cm) long, and individual flowers are about one inch (2.5 cm) long.