Seasonal Portabella Crimini Mushroom Growing Kit Mushroom kit 12"W x 10"D x 9"H The Portabella mushroom is one of the tastiest mushrooms ever grown. . Portabella caps can grow from 3-4" across to as large as 5" in diameter. Best Temperature for Growing: 63 - 68 Keep out of direct sunlight. AVAILABLE SEPT - APRIL ONLY