Citrus trees
Even without the bonus of delightful fruit, citrus would be popular landscape plants for their attractive form, glossy evergreen foliage, and headily fragrant flowers.
Your region’s winter temperatures play an important role in determining what kinds of citrus you can grow. The more common types can be grown outdoors only in the southernmost parts of the United States (Zones 8, 9, 12-27). Lemons, limes, and citrons are generally the most sensitive to freezes; sweet oranges, grapefruit, and most mandarins are intermediate. Kumquats, satsuma mandarins, sour oranges, and calamondins withstand temperatures into the high teens. Hardy citrus, including citrange and ‘Changsha’ mandarin, are good choices for Zones 7, 28-31 (just outside the typical hardiness range).
Heat requirements also play a role in your choice of citrus. Sweet-fruited varieties need moderate to high heat to form sugars, while sour-fruited types require less heat.