Calla vs Mexican Petunia Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Calla
Zantedeschia aethiopica
Zantedeschia aethiopica, commonly known as Calla Lily, is a rhizomatous herbaceous perennial prized for its elegant, trumpet-shaped spathes (modified leaves) that surround a central spadix. While often called a lily, it is not a true lily. It grows from rhizomes, producing large, arrow-shaped, glossy green leaves. It is primarily an outdoor plant, thriving in moist conditions. People grow it for its striking flowers, often used in bouquets and floral arrangements. It can be grown indoors, but requires specific conditions to thrive and may not flower as readily as outdoors.
Mexican Petunia
Ruellia simplex
Mexican Petunia is a fast-growing, herbaceous perennial often grown for its showy, trumpet-shaped flowers that come in shades of purple, pink, and white. It typically reaches a height of 1-3 feet. While visually appealing, it's considered invasive in many regions due to its aggressive spreading nature via rhizomes and seeds. It is primarily an outdoor plant, thriving in warm climates. People grow it for its vibrant flowers and relatively low maintenance in suitable outdoor environments. Indoor cultivation is challenging due to its high light requirements and aggressive growth.
Quick Plant Comparison
| Feature | Calla | Mexican Petunia |
|---|---|---|
| Light | Bright, indirect light to full sun outdoors. Indoors, provide bright indirect light, ideally near an east- or west-facing window. | Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal flowering. |
| Watering | Every 3-7 days during the growing season, less frequently in winter. | Every 3-7 days during the growing season, less frequently in winter. |
| Humidity | 40-60% | 30-50% |
| Temperature | 18-24°C | 18-27°C |
| Care Level | Moderate | Expert |
| Growth Rate | Moderate | Fast |
| Max Height | Indoors: 0.6-1 meter | 0.3-0.9 meters (indoors, likely smaller than outdoors) |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining potting mix rich in organic matter. A mix of peat moss, perlite, and compost is suitable. | Well-draining soil, such as a mix of potting soil, perlite, and sand. |
| Beginner Friendly | With Caution | ❌ No |
| Weekly Maintenance | 10 minutes weekly | 30 minutes weekly (primarily for pruning and controlling spread). |
🔬 Botanical Information — Comparing These Plants
Calla
| Scientific Name | Zantedeschia aethiopica |
|---|---|
| Family | Araceae |
| Native To | South Africa |
| Also Known As | Calla Lily, Arum Lily, Trumpet Lily |
| Leaves | Large, arrow-shaped, glossy green leaves. The leaves can be up to 45 cm long and 25 cm wide. Some varieties have speckled or variegated leaves. |
| Flowers | Can flower indoors with proper care, but more reliably flowers outdoors. The 'flower' is a modified leaf called a spathe, which is typically white, but can also be pink, yellow, orange, or purple. The spadix, the yellow spike in the center, is where the true flowers are located. |
Mexican Petunia
| Scientific Name | Ruellia simplex |
|---|---|
| Family | Acanthaceae |
| Native To | Mexico, South America, and the West Indies |
| Also Known As | Mexican Petunia, Ruellia, Britton's Wild Petunia, Mexican Bluebell |
| Leaves | The leaves are lance-shaped, dark green, and have a slightly serrated edge. They are typically 10-15 cm long and arranged oppositely along the stem. |
| Flowers | It rarely flowers indoors. Outdoors, it produces trumpet-shaped flowers that are typically purple, but can also be pink or white. The flowers bloom throughout the warm months, attracting pollinators. |
📏 Size & Growth — Plant Comparison
Calla
Mexican Petunia
🌱 Propagation — Comparing Plant Growth
Calla
Methods: Division, Seed
Difficulty: Moderate
Tips: Divide rhizomes in early spring before new growth begins. Ensure each division has at least one eye (bud). Plant divisions in well-draining soil and keep moist. Seed propagation is possible but slower.
Mexican Petunia
Methods: Stem cuttings, Division, Seed
Difficulty: Easy
Tips: Stem cuttings root easily in water or directly in soil. Division is best done in spring or fall. Seeds can be sown directly into the ground or started indoors.
✨ Benefits & Features — Comparing Plant Value
Calla
The Calla Lily is not a true lily, but a rhizomatous perennial with a unique spathe and spadix flower structure. Its elegant, trumpet-shaped flowers make it a popular choice for bouquets and floral arrangements. It requires a dormant period in winter to promote flowering in the following season.
- ✓ Aesthetically pleasing flowers.
- ✓ Can be used for cut flower arrangements.
- ✓ Adds a touch of elegance to any room.
- ✓ Can improve mood and reduce stress.
- ✓ Provides a sense of accomplishment through successful care.
- ⚠️ Toxic to pets
Mexican Petunia
Mexican Petunia is known for its ability to thrive in hot, humid conditions and its tolerance of drought once established. Its aggressive spreading habit distinguishes it from many other flowering perennials.
- ✓ Attracts pollinators like butterflies and hummingbirds.
- ✓ Adds vibrant color to the garden.
- ✓ Relatively drought-tolerant once established.
- ✓ Provides a long blooming season.
- ✓ Can be used as a ground cover (with careful management).
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Calla
Mexican Petunia
🌞 Light Requirements
Calla
Bright, indirect light to full sun outdoors. Indoors, provide bright indirect light, ideally near an east- or west-facing window.
Low light tolerant: ❌ No
Mexican Petunia
Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal flowering.
Low light tolerant: ❌ No
💧 Watering Needs
Calla
Keep the soil consistently moist, especially during the growing season. Water thoroughly when the top inch of soil feels dry. Reduce watering in the dormant period. Overwatering can lead to rhizome rot, indicated by yellowing leaves and a foul odor. Underwatering results in wilting and browning leaf tips.
Mexican Petunia
Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. During the growing season, water more frequently. Reduce watering in the winter. Signs of underwatering include wilting leaves; overwatering includes yellowing leaves and soggy soil.
🌡️ Temperature & Humidity
Calla
Temperature: 18-24°C
Humidity: 40-60%
Mexican Petunia
Temperature: 18-27°C
Humidity: 30-50%
🤔 Which Plant Is Right For You?
Calla
Zantedeschia aethiopicaExperienced plant enthusiasts seeking a flowering plant with elegant blooms, willing to provide specific care requirements.
✅ Choose This Plant If...
- You appreciate elegant, trumpet-shaped flowers.
- You can provide bright, indirect light and consistent moisture.
- You are willing to provide a dormant period in winter.
- You are experienced with plant care and can address potential problems.
- You want a plant that can be used for cut flower arrangements.
❌ Skip This Plant If...
- You have pets that may ingest the plant.
- You cannot provide bright light or consistent moisture.
- You are a beginner plant owner.
- You prefer low-maintenance plants.
Mexican Petunia
Ruellia simplexExperienced gardeners in warm climates who want a vibrant, flowering plant for their outdoor space, and are prepared to manage its aggressive growth.
✅ Choose This Plant If...
- You live in a warm climate and want a low-maintenance flowering plant for your garden.
- You want to attract butterflies and hummingbirds to your yard.
- You are experienced with managing aggressive spreaders.
- You have a sunny outdoor space where it can thrive.
- You appreciate its vibrant purple flowers.
❌ Skip This Plant If...
- You have pets who might ingest it.
- You live in a climate where it is considered invasive.
- You don't have a very sunny location.
- You are looking for a low-maintenance indoor plant.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Calla is rated Moderate care level, while Mexican Petunia is Expert.
Calla has moderate growth, while Mexican Petunia grows fast.
💡 Pro Tips For Comparing These Plants
Calla Care Tips
Calla Lilies require bright light and consistent moisture. They can be grown indoors, but may not flower as readily as outdoors. Ensure good drainage to prevent rhizome rot. Toxicity to pets is a significant concern. Requires a dormant period in winter.
- Provide a dormant period in winter by reducing watering and keeping the plant in a cool location.
- Ensure good drainage to prevent rhizome rot.
- Fertilize regularly during the growing season to promote flowering.
- Monitor for pests and diseases and treat promptly.
- Provide bright, indirect light for optimal growth and flowering.
Mexican Petunia Care Tips
Mexican Petunia is primarily an outdoor plant that is difficult to maintain indoors. It requires very bright light, well-draining soil, and careful monitoring of its aggressive growth. It is toxic to pets, so caution is needed if kept indoors.
- Plant in a container to control its spread.
- Provide regular pruning to maintain its shape and size.
- Water deeply but infrequently.
- Fertilize during the growing season to encourage blooming.
- Monitor for pests and diseases and treat promptly.
⚠️ Common Problems & Solutions — Plant Care Comparison
Calla
Mexican Petunia
❓ Frequently Asked Questions — Comparing These Plants
Calla
What are the light requirements for Calla?
Calla lilies thrive in bright, indirect light. Direct sunlight can scorch their leaves, so avoid placing them in south-facing windows without some form of shading. An east- or west-facing window is ideal, providing ample light without the intensity of direct sun. If you notice the leaves becoming pale or the plant failing to bloom, it may not be receiving enough light. In such cases, consider supplementing with artificial grow lights. During the darker winter months, supplemental lighting is particularly beneficial to maintain healthy growth and encourage future blooms. Ensure the light is diffused to prevent leaf burn. Regular rotation of the plant ensures all sides receive adequate light, preventing uneven growth.
How do I care for Calla?
Calla lilies require bright, indirect light for optimal growth and blooming. Water thoroughly when the top inch of soil feels dry, ensuring proper drainage to prevent root rot. During the growing season (spring and summer), fertilize every 2-4 weeks with a balanced liquid fertilizer diluted to half strength to encourage flowering. Reduce watering and fertilization during the dormant period in fall and winter. Maintain a humidity level of 50-60%. Repot annually in spring using well-draining potting mix. Remove spent flowers to encourage more blooms. Monitor for pests like aphids and spider mites, and treat promptly if detected. Provide support for taller varieties to prevent them from bending. Rotate the plant regularly to ensure even growth and prevent leaning towards the light source. Protect from frost and freezing temperatures.
How do I propagate Calla?
Calla lilies can be propagated by division, stem cuttings (though less common), and keiki (small plantlets that sometimes form on the plant).
Mexican Petunia
What are the light requirements for Mexican Petunia?
Mexican Petunias thrive in full sun, requiring at least 6 hours of direct sunlight each day. Adequate sunlight is crucial for abundant blooming. However, they can also tolerate partial shade, especially in hotter climates, where some afternoon shade can prevent leaf scorch. Insufficient light can lead to leggy growth, reduced flowering, and paler foliage.
How do I care for Mexican Petunia?
Mexican Petunias are relatively easy to care for. Place them in a location that receives at least 6 hours of sunlight daily for optimal blooming. Water regularly, especially during hot, dry periods, keeping the soil consistently moist but not waterlogged. Fertilize every 4-6 weeks during the growing season (spring and summer) with a balanced, slow-release fertilizer or a liquid fertilizer formulated for flowering plants.
How do I propagate Mexican Petunia?
Mexican Petunias can be easily propagated through division, stem cuttings, and keiki (small plantlets that form on the stems).
Last updated: April 25, 2026 — Plant care data reviewed and verified by our editorial team.