Cosmos vs Devil's Backbone Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Cosmos
Cosmos bipinnatus
Cosmos bipinnatus is an annual flowering plant typically grown outdoors. It features delicate, fern-like foliage and daisy-like flowers in shades of pink, purple, white, and occasionally yellow or orange. Plants typically reach heights of 1 to 6 feet. Cosmos are popular for their long blooming season, attracting pollinators like bees and butterflies. They are primarily grown for ornamental purposes in gardens and meadows, adding color and texture to landscapes. While relatively easy to grow outdoors, they are not well-suited for indoor cultivation due to their high light requirements and large size.
Devil's Backbone
Euphorbia tithymaloides
Euphorbia tithymaloides, commonly known as Devil's Backbone, is a succulent shrub characterized by its unique zig-zagging stems and fleshy, ovate leaves. It can grow up to 6-8 feet tall outdoors, but typically remains smaller when grown as a houseplant. The leaves are typically green, but variegated forms with white or pink edges are also popular. Small, slipper-shaped red or pink flowers appear sporadically. It's grown for its unusual form and ease of care, though it's important to note its toxicity.
Quick Plant Comparison
| Feature | Cosmos | Devil's Backbone |
|---|---|---|
| Light | Full sun (at least 6-8 hours of direct sunlight daily) | Bright indirect light to partial sun. Avoid intense, direct sunlight, especially during the hottest part of the day. |
| Watering | Every 1-2 weeks, depending on weather and soil drainage | Every 2-3 weeks, depending on environmental conditions |
| Humidity | 30-50% | 30-50% |
| Temperature | 18-27°C | 18-24°C |
| Care Level | Expert | Easy |
| Growth Rate | Fast | Moderate |
| Max Height | N/A (Outdoor plant, unsuitable for indoor growing) | 0.6-1.2 meters (2-4 feet) indoors |
| Pet Safety | ✅ Safe | ❌ Toxic To Pets |
| Soil | Well-draining soil; sandy or loamy soil is ideal | Well-draining succulent or cactus mix |
| Beginner Friendly | ✅ Yes | ✅ Yes |
| Weekly Maintenance | 5 minutes weekly | 5 minutes weekly |
🔬 Botanical Information — Comparing These Plants
Cosmos
| Scientific Name | Cosmos bipinnatus |
|---|---|
| Family | Asteraceae |
| Native To | Mexico |
| Also Known As | Cosmos, Garden Cosmos, Mexican Aster |
| Leaves | The leaves of Cosmos bipinnatus are finely divided and fern-like, giving the plant a delicate and airy appearance. They are typically green in color and arranged oppositely along the stems. The leaves are relatively small, adding to the plant's overall graceful form. |
| Flowers | Cosmos rarely, if ever, flower indoors due to insufficient light. Outdoors, they produce daisy-like flowers with a central disc and ray florets in shades of pink, purple, white, and occasionally yellow or orange. The flowers are typically 2-4 inches in diameter and bloom profusely throughout the summer and fall. |
Devil's Backbone
| Scientific Name | Euphorbia tithymaloides |
|---|---|
| Family | Euphorbiaceae |
| Native To | Central America, South America, Caribbean |
| Also Known As | Devil's Backbone, Zig Zag Plant, Pedilanthus tithymaloides, Redbird Cactus, Christmas Candle |
| Leaves | The leaves are fleshy, ovate, and typically green, although variegated forms with white or pink margins are common. They are arranged alternately along the zig-zagging stems. |
| Flowers | It can flower indoors, producing small, slipper-shaped red or pink flowers. However, flowering is not guaranteed and is more common in mature plants grown in optimal conditions. |
📏 Size & Growth — Plant Comparison
Cosmos
Devil's Backbone
🌱 Propagation — Comparing Plant Growth
Cosmos
Methods: Seed
Difficulty: Easy
Tips: Sow seeds directly into the garden after the last frost or start indoors 4-6 weeks before the last frost. Lightly cover seeds with soil and keep moist until germination.
Devil's Backbone
Methods: Stem cuttings
Difficulty: Easy
Tips: Allow the cut end to callus over for a few days before planting in well-draining soil. Keep the soil slightly moist until roots develop.
✨ Benefits & Features — Comparing Plant Value
Cosmos
Cosmos are known for their delicate, fern-like foliage and daisy-like flowers that come in a variety of colors. They are also highly attractive to pollinators, making them a valuable addition to any garden. Their long blooming season provides continuous color throughout the summer and fall.
- ✓ Attracts pollinators to your garden.
- ✓ Provides beautiful cut flowers.
- ✓ Adds vibrant color to your outdoor space.
- ✓ Easy to grow and maintain.
- ✓ Supports local ecosystems.
- 🐾 Pet Safe
Devil's Backbone
The Devil's Backbone is unique due to its zig-zagging stems and fleshy leaves, which give it a distinctive architectural form. The variegated varieties add further visual interest with their colorful foliage.
- ✓ Adds visual interest with its unique form.
- ✓ Relatively low-maintenance and easy to care for.
- ✓ Drought-tolerant, making it suitable for forgetful plant owners.
- ✓ Can be easily propagated to create new plants.
- ✓ Adds a touch of the desert to your indoor space.
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Cosmos
Devil's Backbone
🌞 Light Requirements
Cosmos
Full sun (at least 6-8 hours of direct sunlight daily)
Low light tolerant: ❌ No
Devil's Backbone
Bright indirect light to partial sun. Avoid intense, direct sunlight, especially during the hottest part of the day.
Low light tolerant: ❌ No
💧 Watering Needs
Cosmos
Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Cosmos are relatively drought-tolerant once established. Signs of underwatering include wilting and drooping leaves. Overwatering can cause yellowing leaves and stem rot.
Devil's Backbone
Allow the soil to dry out completely between waterings. Overwatering can lead to root rot. Water thoroughly when the soil is dry to the touch. Reduce watering frequency during the winter months. Signs of overwatering include yellowing leaves and stem rot. Underwatering can cause leaf drop and shriveling.
🌡️ Temperature & Humidity
Cosmos
Temperature: 18-27°C
Humidity: 30-50%
Devil's Backbone
Temperature: 18-24°C
Humidity: 30-50%
🤔 Which Plant Is Right For You?
Cosmos
Cosmos bipinnatusGardeners looking for easy-to-grow, colorful annuals that attract pollinators.
✅ Choose This Plant If...
- You want a low-maintenance plant for your garden.
- You want to attract butterflies and bees to your yard.
- You need a plant that blooms for a long period.
- You want to add vibrant colors to your outdoor space.
- You want easy-to-grow cut flowers.
❌ Skip This Plant If...
- You don't have a sunny outdoor space.
- You want a plant that thrives indoors.
- You live in a very cold climate with a short growing season.
Devil's Backbone
Euphorbia tithymaloidesSomeone looking for a unique and low-maintenance succulent with an interesting architectural form.
✅ Choose This Plant If...
- You want a low-maintenance plant that doesn't need much attention.
- You appreciate unique and unusual plant forms.
- You have a bright, sunny spot in your home.
- You are looking for a plant that is relatively drought-tolerant.
- You want a plant that is easy to propagate.
❌ Skip This Plant If...
- You have pets or small children who might ingest the plant.
- You are prone to overwatering plants.
- You don't have a bright enough location.
- You are looking for a plant with showy flowers.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Cosmos is rated Expert care level, while Devil's Backbone is Easy.
Cosmos has fast growth, while Devil's Backbone grows moderate.
💡 Pro Tips For Comparing These Plants
Cosmos Care Tips
Cosmos are easy to grow outdoors in full sun and well-draining soil. They are not suitable for indoor growing due to their high light requirements and large size. Attempting to grow them indoors will likely result in leggy, weak plants with few flowers.
- Deadhead spent flowers regularly to encourage more blooms.
- Provide support for taller varieties to prevent them from flopping over.
- Water deeply but infrequently, allowing the soil to dry out slightly between waterings.
- Avoid over-fertilizing, as this can lead to excessive foliage growth and fewer flowers.
- Plant in well-draining soil to prevent root rot.
Devil's Backbone Care Tips
Devil's Backbone is a relatively easy-care succulent that thrives in bright, indirect light and well-draining soil. Avoid overwatering and protect from frost. Be mindful of its toxic sap and keep it away from pets and children.
- Allow the soil to dry out completely between waterings to prevent root rot.
- Provide bright, indirect light for optimal growth and color.
- Fertilize sparingly during the growing season.
- Wear gloves when handling the plant to avoid skin irritation from the sap.
- Rotate the plant regularly to ensure even growth.
⚠️ Common Problems & Solutions — Plant Care Comparison
Cosmos
Devil's Backbone
❓ Frequently Asked Questions — Comparing These Plants
Cosmos
What are the light requirements for Cosmos?
Cosmos require a minimum of six to eight hours of direct sunlight per day to thrive and produce abundant blooms. Insufficient sunlight can result in leggy growth, weak stems, and reduced flowering. Choose a sunny location in your garden or on your balcony where the plants will receive ample sunlight throughout the day. If growing Cosmos indoors, place them near a south-facing window that provides the brightest light. Rotate the plants regularly to ensure even exposure to sunlight on all sides. If natural light is insufficient, supplement with grow lights to provide the necessary light intensity.
How do I care for Cosmos?
Cosmos thrive in full sun and well-draining soil. Water regularly, especially during dry periods, but avoid overwatering to prevent root rot. Fertilize lightly every few weeks with a balanced fertilizer, or a bloom-boosting formula during the flowering season, to encourage abundant blooms. Deadhead spent flowers regularly to promote continuous blooming. Cosmos are generally low-maintenance plants, but they may benefit from staking if they become tall and leggy. Prune them lightly to maintain their shape and encourage bushier growth. Protect them from strong winds, which can damage the delicate stems. Monitor for pests like aphids and treat them promptly if detected. Cosmos are generally annuals, but they may self-seed in some climates.
How do I propagate Cosmos?
Cosmos are most commonly propagated by seed. Sow seeds directly into the garden in spring after the last frost, or start them indoors 6-8 weeks earlier. For division, carefully dig up the plant in early spring or fall and separate the root ball into smaller clumps, ensuring each clump has healthy roots and foliage. Replant the divisions immediately in well-draining soil. Stem cuttings are not a common method for Cosmos, but can be attempted by taking 4-6 inch cuttings from new growth in spring, dipping them in rooting hormone, and planting them in moist potting mix. Keiki propagation is not applicable to Cosmos.
Devil's Backbone
What are the light requirements for Devil's Backbone?
Devil’s Backbone thrives in bright, indirect light. It can tolerate some direct sunlight, especially in the morning or late afternoon, but avoid prolonged exposure to intense midday sun, which can scorch the leaves. An east-facing window is often ideal, providing ample morning light without the harshness of the afternoon sun. A south- or west-facing window can also work, but be sure to filter the light with a sheer curtain or move the plant slightly away from the window to prevent sunburn.
How do I care for Devil's Backbone?
Devil’s Backbone is a relatively easy-to-care-for succulent. Provide it with bright, indirect light, although it can tolerate some direct sun. Water thoroughly only when the soil is completely dry to the touch, typically every 2-4 weeks, depending on environmental conditions. Ensure the pot has drainage holes to prevent root rot. Use a well-draining succulent or cactus potting mix.
How do I propagate Devil's Backbone?
Devil’s Backbone is easily propagated through leaf cuttings, offsets, and stem cuttings.
Last updated: May 1, 2026 — Plant care data reviewed and verified by our editorial team.