Pinching will delay bloom by two to three weeks. Supplemental light from HID lamps benefits growth at 400 ft.ca. Supplemental carbon dioxide also improves growth at 1000-1500 ppm. A 2-3F increase in day temperature should be used with supplemental CO 2 . Low light and low fertility cause mottled foliage.
Water stress causes leaf and flower bud abscision.
Rhizoctonia causes stem rots. Botrytis can be a problem under cool, humid conditions.