In the citrus belt, trees can be planted any time of year. Spring is the best time to plant container-grown trees from a nursery outside.
Standard-size orange and grape fruit trees grow 18 to 22 feet tail; dwarf varieties grow 8 to 12 feet tall. Dwarf varieties are suitable for growing outdoors or in containers.
Most citrus trees begin to bear at 3 to 6 years.
Pollination is generally accomplished by insects and sometimes by the wind. Indoor gardeners can hand-pollinate. Most citrus varieties are self-fertile so you need only one tree.
Citrus will grow in most soils that are moist but well drained. Avoid salty soils.
Choose a site protected from wind, with maximum sun exposure.
Set standard-size trees 12 to 25 feet apart, set dwarfs 6 to 10 feet apart. (Distance will depend on type and variety.) Set standard-size oranges 20 feet apart, standard-size grapefruit 25 feet apart. Limes and lemons require less space.
Plant the trees no deeper than they grew in the nursery container.
Water the entire root area deeply about once a week.
Prune any time of the year. When the trees are young, prune over vigorous growth. Prune mature trees to remove dead, broken, and diseased branches.
Give mature trees 1 to 1 1/2 pounds of nitrogen a year. Apply in four portions throughout the year, or just once 6 to 8 weeks before bloom.
See our article Fruit Pests and Diseases for controls of common citrus pests such as aphids, scale, red spider mites, and gummosis.
Although some varieties ripen their fruit all at once, many others ripen fruit over a period of several months (fall through winter). Taste is the best indicator of ripeness.