Hi Charlie
According to Orchidwiz:
50%-60% humidity. Mature plants MUST dry out between waterings. Grow in a pot with a porous, free-draining media. Fertilize weekly, weakly (one quarter to half the normal dose). Common media: fir bark, tree-fern fiber, expanded clay, lava rock, charcoal or a combination.
Epi. Helen Yamada is composed of species of which 88% take high light and 56% take direct sun light. Grow this hybrid in bright indirect light to full sun conditions.
Epi. Helen Yamada is composed of species of which 94% take intermediate temperatures, 94% take hot temperatures and 6% take cool temperatures. Grow this hybrid in intermediate to hot conditions, or 68°F to 85°F at night.
It's a beauty too!