Before greenhouses were invented, plants and flowers could only be cultivated in the climate they were best adjusted to. This meant that more tropical items were not readily available in colder climates. Transporting the flowers while keeping them alive was exceptionally difficult, and incurred an increased cost as well. Greenhouses create a temporary ecosystem within its glass walls, and works with convection heating to increase the temperature within it. Sunlight that enters through the glass panels is absorbed by the plants and soil, and retained within the building. Abele Greenhouse and Garden Center is a green house in Saginaw that uses this technology to increase the variety of plants they are able to grow and offer. Growing more tropical plants in a controlled environment brings down the costs of such flowers and brings a variety of color to any garden.