The StarterHouse has 4 vent openings in the top to provide optimum air circulation. With the vents open, outside air circulates throughout the Starter-House to prepare plants for planting in outdoor conditions. With the vents closed, your plants remain protected from insects, birds, and other pests, as well as wind, frost, and snow. The Starter-House small greenhouse design is compact and lightweight for easy transport, setup, and take down. The 100 percent weatherproof Gro-Tec materials is UV resistant with rip stop protection for longer life of your greenhouse. The Starter-House is a great cover for a pond with water plants and is perfect for starting seedlings.