Citrus is grown by ‘budding,’ not by planting a seed. This is because trees grown from a citrus seed are often quite different from the mother tree and the trees may be fruitless for many years. To circumvent these problems, growers and researchers grow seedlings from citrus seeds and then tightly splice onto their rootstock seedling a small amount of material, called a bud, from a tree of the desired variety.
True Citrus is not only dried, however. The fresh citrus fruits are first cold-pressed, just like the best olive oil. In cold-pressing, the fruit is crushed with a stainless steel press in which the temperature is controlled so the fruit’s flavor, aroma and nutritional value are preserved. After that, the pure citrus liquid is crystallized through evaporation. The result: crystals of real citrus with peak of freshness flavor.
Citrus grows best in a band 30-40º latitude on either side of the equator. It is a true subtropical crop. Good growing temperatures are 75-80ºF, but 40ºF good for rest, development of acidity, and color. Quality is best where there is a certain amount of low temperature. Peel color is especially related to temperature. Low temperature brings out orange color. Some citrus such as ‘Valencia’ will even regreen if warm temperature interrupt the maturation period. High temperatures lower acidity, and produce larger insipid fruit. Pomelo is the exception to most citrus. It developes good quality and color in high temperatures. Also true for grapefuit, hybrid between pomelo and sweet orange.
Citrus is first mentioned in Chinese literature in 2200 BCE . First citrus in Europe seems to have been the citron, a fruit which has religious significance in Jewish festivals. It was mentioned in 310 BCE by Theophrastus. Lemons and limes and sour orange may have been mutations of the citron. The Romans grew sour orange and lemons in 50-100 CE ; the first mention of sweet orange in Europe was made in 1400. Columbus brought citrus on his second voyage in 1493 and the first plantation started in Haiti. In 1565 the first citrus was brought to the US in St. Augustine.
Citrus growers want to make sure a tree stays strong and healthy from the very beginning of its life. So they take a bud (twig or stem from another citrus tree) and insert into a sturdy root stock. This process is called “grafting”.
Citrus fruits — including oranges, tangerines, lemons, limes and grapefruits — come from citrus trees.
Citrus normally grows and produces well without undue attention or difficulty but occasional problems do occur.
Citrus grows best in full sunlight, but place container-grown citrus to receive partial shade to reduce growth and to provide better acclimation to the occasional trips indoors during winter. Avoid extremely low light for prolonged periods as the trees will become leggy and unattractive.
Citrus trees generally do not perform well as houseplants, but several kinds can be adapted to container culture. However, none will be as attractive or grow and fruit as well as trees grown under optimal conditions in the soil.