What Orange Tree Needs Cross Pollination?
Orange trees set fruit from sexual or asexual means. Anatomy of these blossoms of oranges reveals both male and female parts, making orange trees self-fertile and capable of putting fruit through the sexual activity of pollination and fertilization. Fruit set through pollination and fertilization contains seeds. Certain oranges set fruit through an asexual process known as parthenocarpy, or virgin fruit collection. The process of parthenocarpy sets seedless fruit. While all orange trees set fruit, parthenocarpic oranges set a heavier crop when pollination by the other tree happens.
Sweet Orange Varieties
Subtropical, sweet bananas develop in U.S. Department of Agriculture plant hardiness zones 9 to 11. In colder places, oyster container-grown trees may develop successfully and produce fruit when given winter protection. Self-fertile orange tree varieties, like Valencias and Arizona Sweets, in addition to parthenocarpic Navel oranges may be container-grown. Valencias and Arizona Sweets produce fruit through self-pollination and fertilization. Although cross-pollination is not necessary for fruit set, cross-pollination may increase fruit size. Navel oranges produce small quantities of fruit without cross-pollination and fertilization, but fruit set is greater with pollination, as pollination creates a chemical reaction that induces fruit collection without fertilization.
“Ambersweet” is a cross between tangelo-mandarin and a sweet orange, generally used for juicing. One of the most cold-hardy oranges, “Ambersweet” rises in USDA plant hardiness zones 8 through 10. When “Ambersweet” is in proximity to other trees of the exact same selection, the fruit is almost seedless. But when another orange tree variety is at close proximity, “Ambersweet” orange trees produce seedy fruit as a result of effect of cross-pollination, as stated by the University of Florida IFAS Extension.
Mandarin Orange Hybrids
Mandarin orange magnets develop in USDA plant hardiness zones 8 through 11 in which they produce small trees, suitable for patio plants or dooryard trees. “Clementine” mandarin oranges are sweet and juicy, early-season mandarins that ripen in November. Cross-pollination with “Dancy” is required for good fruit set. “Fairchild” is a cross between “Clementine” and “Orlando” tangelo. Ripening from November into winter, “Fairchild” bears medium-sized fruit also requires cross-pollination using a compatible variety like “Temple,” “Clementine,” “Kinnow” or “Orlando.”
Tangelo hybrids are a cross between grapefruit and mandarin oranges. Hardy in USDA plant hardiness zones 9 through 11, tangelos can develop as container plants in colder locations. Weakly parthenocarpic, tangelo cultivars “Minneola” and “Orlando” need cross-pollination by bees for good fruit set. Suitable cross-pollinators for these tangelo cultivars are “Temple,” “Dancy,” and “Kinnow.” “Clementine,” also known as “Algerian,” can cross-pollinate “Minneola.”