Lemon trees are popular decorative trees even in climates where they will not bear fruit. However, before you purchase and plant a lemon tree, you need to have a good idea of what kind of tree it will turn into. This will be based partly on the plant itself and partially on the care you give it.
Lemon trees tend to grow to heights of 10 to 20 feet. They will remain smaller than this--possibly 4 to 9 feet--if you grow them in pots instead of in the ground. Left unshaped, lemon trees will grow into ovoid shapes with branches that reach up and out. Trunks can get quite thick and the branches may have thorns on them when the trees reach maturity.
Flowers and Fruit
In warm climates or if brought indoors for the winter months, lemon trees will flower and bear fruit periodically throughout the year. However, most lemon trees produce the most flowers and fruit during the summer. If your lemon tree grows outside year-round but is exposed to cold winters, then it may flower but fail to produce fruit, or it may produce lush foliage but fail to flower. Lemon fruits are oval, rich yellow and should be firm but not hard to the touch when ripe. The flowers are mildly fragrant and grow alone or in clusters. The petals are white on the top and flushed violet underneath.
Climate, Soil and Cultivation Habits
Lemon trees need well-drained soil because they are extremely susceptible to root rot. They prefer climates where the temperature does not fall below freezing, but they can live in colder climates though they may not fruit or flower. Temperatures below 20 degrees F will kill them. Lemon trees like acidic soils with pH of 5.5 to 6.5. You can add lime to adjust the pH without hurting the tree, although they do not generally respond well to peat or fertilizers, other than a little ammonium sulfate, until after they have reached one year of age.