North America Native Plant

Sour Orange

Botanical name: Citrus ×aurantium

USDA symbol: CIAU8

Life cycle: perennial

Habit: shrub

Native status: Non-native, reproduces and persists in the wild in the lower 48 states âš˜ Non-native, reproduces and persists in the wild in Navassa Island âš˜ Non-native, reproduces and persists in the wild in Puerto Rico âš˜ Non-native, reproduces and persists in the wild in the U.S. Virgin Islands  

Sour Orange: A Fragrant Citrus for Warm Climate Gardens If you’ve ever caught a whiff of intoxicatingly sweet citrus blossoms on a warm spring evening, you might have encountered a sour orange tree. Known botanically as Citrus ×aurantium, this evergreen beauty has been charming gardeners for centuries with its glossy ...

Sour Orange: A Fragrant Citrus for Warm Climate Gardens

If you’ve ever caught a whiff of intoxicatingly sweet citrus blossoms on a warm spring evening, you might have encountered a sour orange tree. Known botanically as Citrus ×aurantium, this evergreen beauty has been charming gardeners for centuries with its glossy leaves, fragrant flowers, and bright orange fruit that’s too tart for most people’s taste buds but perfect for marmalade makers.

What Exactly is a Sour Orange?

The sour orange is a perennial shrub that typically grows as a multi-stemmed woody plant, usually staying under 13-16 feet in height. Don’t let the name fool you – while the fruit might pucker your lips, this plant is anything but sour when it comes to garden appeal. Its glossy, dark green leaves provide year-round interest, while the intensely fragrant white flowers that appear in spring are absolutely divine.

Where Does It Come From?

This citrus charmer isn’t native to North America – it’s actually a hybrid that originated in Southeast Asia. However, it has made itself quite at home in warmer parts of the United States, where it now reproduces spontaneously in the wild. You’ll find established populations in Florida, Georgia, Texas, Puerto Rico, the Virgin Islands, and even Navassa Island.

Should You Plant a Sour Orange?

Here’s where things get interesting. While sour oranges aren’t native to North America, they’re not currently classified as invasive either. This puts them in a gray area for native plant enthusiasts. If you’re committed to supporting local ecosystems, you might want to consider native alternatives like native citrus species or other fragrant flowering shrubs native to your region.

That said, if you’re drawn to the sour orange’s unique charms, it can be a lovely addition to the right garden, especially since it does provide some benefits to pollinators with its nectar-rich flowers.

Garden Role and Landscape Uses

Sour oranges are wonderfully versatile in the landscape. Here are some ways you might use them:

  • As a specimen plant in Mediterranean or subtropical gardens
  • In container gardens on patios or courtyards
  • As an informal hedge or screen
  • In citrus groves as rootstock for other citrus varieties

Growing Conditions and Care

If you decide to grow a sour orange, you’ll need to live in USDA hardiness zones 9-11, as these plants need warm climates to thrive. Here’s what they prefer:

  • Sunlight: Full sun for best flowering and fruiting
  • Soil: Well-draining soil is essential – they hate wet feet
  • Water: Regular watering, but allow soil to dry between waterings
  • Climate: Warm temperatures year-round; protect from frost

Planting and Care Tips

Spring is the ideal time to plant your sour orange. Choose a sunny spot with excellent drainage, and dig a hole twice as wide as the root ball but no deeper. Water regularly during the first growing season to establish roots, then settle into a routine of deep, infrequent watering.

Annual pruning after fruiting helps maintain shape and promotes healthy growth. Remove any dead, damaged, or crossing branches, and don’t be afraid to trim for size – these plants respond well to pruning.

Wildlife and Pollinator Benefits

While we don’t have extensive data on wildlife benefits, the fragrant flowers do attract bees and other pollinators during blooming season. The nectar-rich blossoms provide an early spring food source when many other plants are still dormant.

Wetland Considerations

Sour oranges prefer upland conditions and rarely occur in wetlands. In most regions where they grow, they’re classified as Facultative Upland or Obligate Upland, meaning they stick to well-drained, non-wetland areas – which aligns perfectly with their cultural requirements.

The Bottom Line

Sour oranges can be delightful garden additions in warm climates, offering year-round foliage, heavenly scented flowers, and colorful (if inedibly tart) fruit. While they’re not native, they’re currently not problematic either. If you choose to grow one, you’ll be rewarded with a relatively low-maintenance plant that adds Mediterranean flair to your landscape. Just remember to consider native alternatives first, and if you do plant one, enjoy those incredible spring blooms – your local bees certainly will!

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" matching plants to their ideal growing conditions, so they'll thrive with less work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Atlantic and Gulf Coastal Plain

FACU

Facultative Upland - Plants with this status usually occurs in non-wetlands but may occur in wetlands

Caribbean

UPL

Obligate Upland - Plants with this status almost never occurs in wetlands

Great Plains

FACU

Facultative Upland - Plants with this status usually occurs in non-wetlands but may occur in wetlands

Sour Orange

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Sapindales

Family

Rutaceae Juss. - Rue family

Genus

Citrus L. - citrus

Species

Citrus ×aurantium L. (pro sp.) [maxima × reticulata] - sour orange

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA