Mexican Petunia

Ruellia simplex

Mexican Petunia is a fast-growing shrub, hardy in USDA zones 8-10, that matures to about 3-4 ft × 2-3 ft. It does best in full sun and part shade with high water needs in well-drained, moist and occasionally-wet soil. Expect purple blooms in fall and summer. It attracts butterflies and hummingbirds, stands up well to deer, drought and heat.

⚠ Restricted in FL, TX, SC, GA, AL, LA

Invasive in the Southeast — it spreads by ejecting seed and escapes gardens easily.

USDA zones: 8-10
Sun: Full sun, Part shade
Water: High
Mature size: 3-4 ft × 2-3 ft
Spacing: 3 feet-6 feet
Growth rate: Fast
Maintenance: Medium
Soil: Well-drained, Moist, Occasionally-wet
Foliage: Green, Purple
Bloom color: Purple
Bloom season: Fall, Summer
Attracts: Butterflies, Hummingbirds
Tough against: Deer, Drought, Heat, Humidity, Wet soil
Watch out for: Spreads weedily
Native to: Caribbean, Central and South America, Mexico

Freeze survival

Will it survive your winters?

We score Mexican Petunia’s freeze-trouble range against the real coldest nights your area has recorded.

Powered by ~35 years of daily lows from the nearest NOAA weather station. A risk read, not a guarantee — a sheltered spot or mature plant beats the odds.