Dr. Mark Dimmitt is the retired Curator of Plants at the Arizona-Sonora Desert Museum in Tucson.
He is world famous in succulent growing circles for his Adenium hybrids. These are plants in the oleander family from southern African through the Arabian Peninsula. He is also a master orchid grower, with many AOS awards.
Today he hosted the Tucson Orchid Society and Desert Valley Orchid Society for an open house. He was inspired to do this because his Dendrobium anosmum (formerly superbum) are in flower. Each of these plants is a different clone, and each is well over 6 feet / 2 meters from base to tip:
Next to these Den. primulinum was just opening its flowers:
They are mounted on wood frames. Like many orchids in the greenhouse, they are watered via drip irrigation.
He has separate reverse osmosis and tap water irrigation systems, with and without a fertilizer injector.
He said the anosmum plants are 5-10 years old from keikis. The wood frames rot, and one day he walks into his greenhouse to find the plant shattered on the floor. He restarts a new plant by attaching a keiki to a new wood frame, and discards the old plant. They reach this size in 3-5 years.