The Portabella mushroom is one of the tastiest mushrooms ever grown. When harvested as a mature mushroom, with the gills exposed, it is called a Portabella. The thick cap on the Portabella is meaty and is wonderful to cook with. Portabella caps can grow from 3-4" across to as large as 5" in diameter. Our mushroom kit grows several crops of this delicious mushroom. The first two crops are usually very large completely filling the box with mushrooms. The third crop is fairly big as well. The subsequent crops after that get smaller fruiting in clusters and lesser amounts, until the mushrooms finally stop. Product SpecificationsBest Temperature for Growing: 63 - 68 degrees Fahrenheit. Keep out of direct sunlight.