Plant guide

Mexican petunia.

Ruellia simplex

Pronounced roo-EL-ee-uh SIM-pleks

Also known as Britton's Wild Petunia, Mexican Ruellia, Mexican blue-bells, Mexican bluebell, Mexican petunia, Softseed wild petunia, Spanish-ladies

The Mexican petunia is a tough, fast growing perennial that brings a splash of color to your garden. It is quite adaptable and thrives in many different conditions. You will love how easily it spreads to fill in empty spots.

At a glance

Care level: Easy
Plant type: Perennial
Light: Full sun to partial shade
Indoor light: Bright indirect
Water: Every 3 to 7 days
Mature size: 3 to 4 feet
Growth rate: Fast

Care

Keep the soil consistently moist to help this plant bloom its best. Watch for wilting leaves, which indicate the plant needs a drink. It is a vigorous grower, so keep an eye on it if you are planting it in the ground.

Watering: Water whenever the top inch of soil feels dry to the touch.
Feeding: Apply a balanced liquid fertilizer every two months during the growing season.
Pruning: Trim back the stems after flowering to encourage a bushier shape and more blooms.
Repotting: Move to a larger container once the roots begin to circle the bottom of the pot.
Soil: Well draining loamy soil
Soil pH: 6.0 to 8.0

Safety

Pets: This plant is generally considered non toxic to cats and dogs.

How to identify it

Lance shaped dark green leaves
Trumpet shaped purple or blue flowers
Slender upright stems
Veined foliage texture

Science

Family: Acanthaceae
Genus: Ruellia
Order: Lamiales
Class: Magnoliopsida

Taxonomy resolved against GBIF.

Is your mexican petunia looking unwell?

This page is a general guide. Pocket Botanist diagnoses problems from a photo of your actual plant, works out watering for your light and conditions, and reminds you when care is due.

Get the app

This guide was generated with AI and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.