A citrus tree is a plant from the genus citrus, which includes flowering plants that often produce fruit. Citrus includes oranges, lemons, grapefruits and limes. Citrus is used in both commercial fruit production and for the individual outdoor garden. Citrus is also suitable for containers when trained to grow small through constant pruning.
Citrus trees, states the University of Texas A&M, are tropical to subtropical in their weather needs. Citrus trees are generally drought tolerant, but require establishment before they can withstand extreme water stress. Protection against cold weather is necessary, as frozen branches will not produce fruit. A soil bank, where dirt is mounded up around the trunk, will protect new trees from damage.
Citrus trees require a small amount of regular pruning in their early stages to promote the best fruit growth. The University of Florida Extension recommends pinching off any sprouts that occur on the rootstock. When young, sprouts are tender and are easily removed, while older sprouts harden off and require cutting with pruning shears. Pruning is required to control the size of the tree and for the removal of diseased or damaged branches.
Citrus trees require a large amount of water for successful fruit production. According to the University of Florida Extension, trees in a commercial citrus orchard consume between 10 to 90 gallons of water per day for each tree. Young trees require irrigation twice a week between the months of March and June to keep the top layer of soil where the roots exist moist. Growth in the cooler months requires half the trees normal water needs.
Common pests of the citrus tree include aphids, whiteflies, fire ants, mites, plant bugs and chewing insects such as grasshoppers. Aphids and whiteflies are most attracted to young spring leaves of the tree and are more likely to attack at this time. Severe attacks by aphids stunt growth and reduce fruit production. Pesticides sprayed early in the spring are the best prevention.
Greasy spot, citrus scab, melanose and foot rot are all common diseases associated with citrus trees. Greasy spot shows up as a greasy film that appears on the leaves of the tree. Tree growth is stunted and become weakened, making them susceptible to other disease. Citrus scab appears as lesions on the fruit skin and the citrus tree leaves. Caused by a fungus, this disease distorts tree limbs and severely reduces growth. Melanose causes small, red lesions that are bumpy along the leaves. Also caused by fungus, this fungal spore inoculates when it rains throughout April through June. Foot rot, finally, causes water-soaked splotches on the bark of the plant that dry out and crack, exposing the inner bark of the tree.