A homemade greenhouse can be a versatile and inexpensive way to not only grow vegetables and flowers, but to extend the growing season when it is too cold outside for plants to thrive. Greenhouses trap heat and help protect plants from insects and disease. Building a greenhouse can be as elaborate as erecting a traditional framed structure with fiberglass panels or as simple as throwing some plastic over a homemade frame. Greenhouse also can be the extra spot that will add beauty to your backyard. Enjoy the greenhouse ideas pictures here!