The long-standing tradition of using greenhouses to grow fruit trees in otherwise inhospitable climates has been around since ancient Rome, where gardeners devised a means of growing lemon trees during unseasonable weather by building greenhouses with translucent windows made of mica. In the court of Louis XIV, the first orangerie provided the scent of orange tree blossoms, year-round. If you have access to a greenhouse, then no matter your latitude, you can plant one of your favorite fruit trees.
For an easy-to-peel alternative to the orange, the mandarin orange tree (Citrus reticulata Blanco) grows exceptionally well in a greenhouse, no matter the outdoor temperature. The mandarin adapts to cooler climates more readily than the orange tree, making it an excellent choice for cool climates or for beginners at greenhouse growing. The mandarin family includes the mandarin fruit as well as tangerines and satsumas; the three varieties have in common thin peels that loosely encase sweet, segmented fruit.
Meyer Lemon Trees
For a lemon tree with large and slightly sweet fruit, plant the Meyer lemon (Citrus meyeri) in your greenhouse. Not true lemons, Meyer lemons have a rich orange-yellow color and a mellow flavor, less acidic than regular lemons. The fruit has a moderate to high amount of seeds and is similar to an orange in color and shape. The tree grows well when potted and produces a high yield, given the tree's relatively low maintenance. It has no thorns. Additionally, it grows well as a cool-climate greenhouse plant, being more resistant to cold than other lemons.
If you enjoy the rich and creamy texture of mango fruit, but don't like paying the high price tag for its exotic status, plant your own mango tree in a greenhouse. The mango (Mangifera indica) produces large ovate or kidney-shaped fruits, measuring from 2 to 9 inches in length and ranging in color from pale green and yellow to intense reds and purples. Several cultivars of mango are bred to do exceptionally well in greenhouses; for best results, select from the Cambodiana, Carabao, Doubikin, Haden, Mulgoba, Paheri or Zill varieties. If space is limited, select a dwarf cultivar. Provide plenty of air circulation and space around the tree to avoid disease. Mango trees require high levels of watering until fruit harvest. Don't allow the greenhouse to become too damp, and force the air to circulate by using fans, ventilation or a passive conduction system.