I recently moved and now have a southern facing window that I want to grow some cattleyas, oncidiums and phals. My light meter reads about 4,000-6,000 fc's in the morning (with a sheer curtain) from about 7-11 in the morning. After this period of time however, the light drops to 1500-50 fc's.
Is only 4 hours of peak light enough to bloom the higher light stuff like the cattleyas?