Citrus

A broadleaf-evergreen citrus tree reaching 15-30 feet tall and wide, with glossy foliage, sharp thorns on its twigs, and highly fragrant white four-petaled flowers. The large fruit (over 3 inches across) ripens pale yellow, often patched with pink, over juicy flesh that ranges from near-white to deep red by cultivar. A subtropical tree hardy only to USDA zone 9a, it is grown outdoors across the citrus belt and as an overwintered container plant farther north.

A vigorous, shade-intolerant small evergreen tree (or large shrub) native to tropical southeastern Asia, grown for very juicy, aromatic green-to-yellow fruit with a thinner rind than Persian lime. Glossy, leathery, distinctively aromatic leaves frame showy five-petaled white flowers — purple-tinged when new — that can appear across all four seasons in warm climates. Strictly tender: NC State lists it for USDA zones 9a-11b, and it does not tolerate standing water, flooding, or shade.

The leading acid citrus — a small broadleaf-evergreen tree to 10-20 feet, usually armed with sharp thorns on the twigs, bearing fragrant white flowers (purplish beneath) that ripen into the familiar oval, nipple-tipped yellow fruit dotted with aromatic oil glands. A tender subtropical: hardy outdoors only in USDA zones 9-11, but a classic large-container plant that can summer outside and overwinter indoors in colder climates. Native to Asia, not North America.

A small subtropical evergreen tree grown for its sweet, fragrant fruit and glossy aromatic leaves. Originally domesticated in subtropical Asia from a cross between a mandarin and a pomelo, it carries clusters of up to six fragrant creamy-white flowers in early spring that ripen into round-to-oval orange fruit 2-5 inches across. Hardy outdoors only in the warmest US zones (9-11) but readily grown as a container plant brought indoors for winter in colder climates.