It is hard to imagine a world without lemons to flavor our tea, meringue pies and puddings--or to scent our cleaning products, candles and perfumes. However, the lemon tree (Citrus limon) is not a naturally occurring plant. According to Filmore Piru Citrus, it is most likely a hybrid of two wild species, lime and citron, and was brought to Spain and northern Africa from the Middle East at some point in the Middle Ages.
Lemons are attractive trees with deep green, glossy leaves and an abundance of long thorns. The five-petaled white flowers are slightly waxy to the touch and highly fragrant. The lemon tree is not a particularly large tree, growing only to about 20 feet when not pruned. Dwarf varieties range from 4 to around 10 feet in height.
Lemons, like most citrus, do well in tropical to subtropical environments--preferring temperatures well above freezing year round. They go dormant when temperatures fall below 52 degrees Fahrenheit and they will freeze if temperatures fall below 27 to 28 degrees F. Since they also prefer a relatively high humidity, lemons do best in California, Florida and parts of Texas in the U.S., as well as in the Mediterranean countries and parts of northern Africa.
Unless you live in one of the optimal growing areas, you should consider growing your lemon trees in containers or in a greenhouse or other sheltered environment. Plant in a fairly acidic soil (pH 6.2 to 6.5) and use plenty of rich compost for the initial planting. Sunkist suggests, in its growing information, that lemons are heavy feeders, requiring relatively large amounts of nitrogen, phosphorous, potassium, sulfur and calcium, as well as smaller quantities of trace minerals. Lemons also prefer a well-drained soil, so be sure to include drainage holes in pots.
As hybrids, lemon trees do not grow true to type from seed, therefore most are grown from grafts of named cultivars to other citrus rootstock. Home gardeners should consider purchasing named varieties rather than attempting to grow their own from seed. In the United States, Eureka, Lisbon, Genoa, Sicily, Belair, and Villafranca are the most common varieties grown commercially. However, the Meyer lemon is a dwarf variety prized by gourmets; since it is small enough to grow in a large pot, it is a favorite of many gardeners. Other good choices for home gardens are La Valette, Quaitre Saisons, Imperial and Ponderosa.
Lemons are high in Vitamin C. As such, they were valuable aboard ships in centuries past to help prevent scurvy among vitamin-deficient sailors, who spent long months at sea with few fresh vegetables. During the 1849 Gold Rush, miners are reputed to have paid large sums for a single lemon in order to ward off vitamin C deficiencies. Lemon juice also has anti-bacterial properties. When added to tomatoes and other foods during the canning process, lemon juice raises acidity and helps retard spoilage.