Mexican Orange

'Bloom start'

Choisya ternata

Rutaceae · broadleaf evergreen shrub · introduced

Last updated

Mexican orange (Choisya ternata, Rutaceae) is a broadleaf evergreen shrub from the southwestern United States and Mexico, reaching 5 to 8 feet tall with a dense, rounded form. Trifoliate leaves (three glossy leaflets) emit a basil-like aromatic odor when crushed. Fragrant white flowers appear in terminal corymbs over an extended bloom period from May through September, with some repeat flowering.

Mexican orange grows in full sun on well-drained, acid, moist soil with shelter from cold winter winds, hardy in Zones 7a to 8b. It is rabbit-resistant and becomes drought tolerant once established. Prune after flowering. Ramorum leaf blight and shoot dieback is the primary disease concern; root and crown rot may occur in poor drainage. The cultivar 'Sundance' offers golden foliage at 5 feet.

Quick Facts

Height
5–8 ft
Spread
4-8 ft
Growth Rate
Medium
Light
Full Sun
Soil
Well Drained To Moist
Water
Moderate
Hardiness
Zone Zones 7a–8b
Bloom Time
May to September
Origin
the southwestern U

Field Observations

Choisya ternata - bloom
Field Observation
Choisya ternata · Mexican Orange
bloom
April 27, 2026 · Kent · 1,624 GDD₃₂ · BBCH 61

Phenological Calendar

As of May 15, 2026, Puget Sound stations range from 1942.5 to 2137.2 GDD₃₂. Mexican Orange has passed 'bloom start' (1624 GDD₃₂).

Regional Season Tracker

GDD₃₂ accumulation across 7 Puget Sound stations · as of May 15, 2026
Station GDD₃₂ Current Stage Next To Go
Issaquah / East King 2,137 'Bloom start'
Kent / Auburn 2,130 'Bloom start'
Seattle / UW 2,102 'Bloom start'
Olympia / Tumwater 2,064 'Bloom start'
Tacoma / Puyallup 2,033 'Bloom start'
Bellingham / Whatcom 2,012 'Bloom start'
Sequim / Rain Shadow 1,943 'Bloom start'
Stage GDD32 Typical Window
'Bloom start' BBCH '61' NOW 1624 'Late April'

Source: 'Field observation, Kent, WA, 2026-04-27' About GDD₃₂ →

Season tracker for Kent / Auburn as of May 15, 2026. Predicted dates use 16-day weather forecast through May 31, 2026, then climate normals.

Diseases: Regionally Documented (1)

Cultivars (1)

'Sundance'
Common name: Sundance Mexican Orange Golden-leaf Mexican Orange; Mature height: 5 ft
Hardy to USDA Zone 7
Data Maturity
Structured Multiple sources. Expert review underway.