Devil's Backbone vs Perennial Flax Plant Comparison

Compare these two plants side by side — care needs, key differences, and which is right for your home.

Devil's Backbone

Devil's Backbone

Euphorbia tithymaloides

VS
Perennial Flax

Perennial Flax

Linum perenne

Devil's Backbone

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.

Euphorbiaceae Central America, South America, Caribbean
✨ Features: Unique zig-zag stems, variegated foliage options
📖 Read Complete Devil's Backbone Guide
Perennial Flax

Perennial Flax

Linum perenne

Perennial Flax (Linum perenne) is a herbaceous perennial known for its delicate, airy appearance and profuse display of sky-blue flowers. It typically grows to a height of 30-60 cm. The plant features slender stems and narrow, lance-shaped leaves. While primarily an outdoor plant, it is grown for its ornamental value in gardens and meadows, attracting pollinators. The flowers are short-lived, opening in the morning and closing by afternoon, but the plant produces a continuous succession of blooms throughout the flowering season. It is not naturally an indoor plant.

Linaceae Europe, North Africa, Asia
✨ Features: Attracts pollinators, drought-tolerant once established
📖 Read Complete Perennial Flax Guide

Quick Plant Comparison

Feature Devil's Backbone Perennial Flax
Light Bright indirect light to partial sun. Avoid intense, direct sunlight, especially during the hottest part of the day. Full sun
Watering Every 2-3 weeks, depending on environmental conditions Every 7-10 days, depending on weather and soil drainage
Humidity 30-50% 30-50%
Temperature 18-24°C 15-24°C
Care Level Easy Expert
Growth Rate Moderate Moderate
Max Height 0.6-1.2 meters (2-4 feet) indoors N/A (Outdoor plant, not suitable for indoor growing)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining succulent or cactus mix Well-draining, sandy or loamy soil
Beginner Friendly ✅ Yes ❌ No
Weekly Maintenance 5 minutes weekly 5 minutes weekly

🔬 Botanical Information — Comparing These Plants

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.

Perennial Flax

Scientific Name Linum perenne
Family Linaceae
Native To Europe, North Africa, Asia
Also Known As Perennial Flax, Blue Flax, Flax
Leaves Narrow, lance-shaped leaves, typically blue-green in color, arranged alternately along the stems.
Flowers Flowers are typically sky-blue, about 2.5 cm in diameter, with five petals. They open in the morning and close by afternoon. Rarely flowers indoors.

📏 Size & Growth — Plant Comparison

Devil's Backbone

Height 0.6-1.2 meters (2-4 feet) indoors
Spread 0.3-0.6 meters (1-2 feet)
Growth Rate Moderate
Growth Pattern It grows as an upright, branching shrub with zig-zagging stems. New growth emerges from the tips of the stems.

Perennial Flax

Height N/A (Outdoor plant, not suitable for indoor growing)
Spread 30-45 cm
Growth Rate Moderate
Growth Pattern Upright, clumping perennial with slender stems and airy foliage.

🌱 Propagation — Comparing Plant Growth

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.

Perennial Flax

Methods: Seed, Division

Difficulty: Easy

Tips: Sow seeds in spring or fall. Divide established plants in spring or fall. Ensure good drainage for successful propagation.

✨ Benefits & Features — Comparing Plant Value

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

Perennial Flax

Perennial Flax is known for its delicate, blue flowers that open in the morning and close by afternoon. It is a relatively low-maintenance perennial that attracts pollinators and is drought-tolerant once established.

  • ✓ Attracts pollinators like bees and butterflies.
  • ✓ Adds a delicate, airy texture to the garden.
  • ✓ Provides a long season of blue flowers.
  • ✓ Drought-tolerant once established, reducing water needs.
  • ✓ Relatively low-maintenance, freeing up gardening time.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Devil's Backbone

Repotting Every 2-3 years, or when the plant becomes root-bound
Pruning Prune to maintain shape and remove any dead or damaged stems.
Fertilizing Balanced liquid fertilizer diluted to half strength, applied every 2-3 months during the growing season (spring and summer)
Seasonal Care Reduce watering in winter during dormancy. Provide bright light year-round.

Perennial Flax

Repotting N/A (Outdoor plant)
Pruning Deadhead spent flowers regularly to encourage continued blooming. Cut back stems in fall after flowering.
Fertilizing Balanced slow-release fertilizer in spring
Seasonal Care In spring, apply a balanced fertilizer. In summer, deadhead spent flowers to encourage more blooms. In fall, cut back stems after flowering. In winter, provide protection from excessive moisture.

🌞 Light Requirements

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

Perennial Flax

Full sun

Low light tolerant: ❌ No

💧 Watering Needs

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.

Perennial Flax

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Ensure good drainage. Signs of underwatering include wilting and yellowing leaves. Overwatering can cause root rot and fungal diseases.

🌡️ Temperature & Humidity

Devil's Backbone

Temperature: 18-24°C

Humidity: 30-50%

Perennial Flax

Temperature: 15-24°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Devil's Backbone

Devil's Backbone

Euphorbia tithymaloides
Care: Easy Time: 5 minutes weekly Beginner: Yes

Someone 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.
📍 Ideal Location: Bright windowsill, sunroom, or well-lit shelf
🎨 Style: Modern, Bohemian, Southwestern
🏠 Apartment Friendly: Yes
⚠️ All parts of the plant contain a milky sap that is toxic if ingested or comes into contact with skin or eyes. Can cause irritation, vomiting, diarrhea, and dermatitis in dogs, cats, and horses.
Perennial Flax

Perennial Flax

Linum perenne
Care: Expert Time: 5 minutes weekly Beginner: No

Gardeners looking for a low-maintenance, flowering perennial for sunny locations.

✅ Choose This Plant If...

  • You want a low-maintenance perennial for a sunny garden.
  • You want to attract pollinators to your garden.
  • You appreciate delicate, blue flowers.
  • You have well-draining soil.
  • You live in a climate with mild winters.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You don't have a sunny outdoor space.
  • You are looking for an easy indoor plant.
📍 Ideal Location: Sunny garden bed or border
🎨 Style: Cottage, Naturalistic, Mediterranean
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, flax (Linum species) is toxic to dogs, cats, and horses. The toxic principle is cyanogenic glycosides. Symptoms include vomiting, diarrhea, weakness, and difficulty breathing. The seeds are the most toxic part.

🎯 Quick Verdict

Best for Beginners Devil's Backbone
Pet Friendly Neither - caution
Less Maintenance Devil's Backbone
Apartment Friendly Devil's Backbone

⚡ Key Differences Between These Plants

🎯

Devil's Backbone is rated Easy care level, while Perennial Flax is Expert.

📈

Devil's Backbone has moderate growth, while Perennial Flax grows moderate.

💡 Pro Tips For Comparing These Plants

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.
❄️ Winter: Reduce watering frequency during the winter months as the plant's growth slows down. Ensure the plant is protected from cold drafts and temperatures below 10°C.
☀️ Summer: Provide adequate ventilation and avoid exposing the plant to intense, direct sunlight during the hottest part of the day. Water more frequently as the soil dries out faster in warmer temperatures.

Perennial Flax Care Tips

Perennial Flax is primarily an outdoor plant and is challenging to grow indoors due to its high light requirements. It needs full sun and well-draining soil. Indoor attempts often result in leggy growth and poor flowering. It is toxic to pets.

  • Ensure well-draining soil to prevent root rot.
  • Provide full sun for optimal flowering.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Apply a balanced fertilizer in spring.
  • Protect from excessive moisture in winter.
❄️ Winter: Cut back stems after flowering. Provide protection from excessive moisture.
☀️ Summer: Deadhead spent flowers regularly to encourage more blooms. Water thoroughly when the top inch of soil feels dry.

⚠️ Common Problems & Solutions — Plant Care Comparison

Devil's Backbone

Common Issues: Root rot, mealybugs, spider mites, leaf drop
Solutions: Root rot: Improve drainage and reduce watering frequency. Mealybugs/Spider mites: Treat with insecticidal soap or neem oil. Leaf drop: Adjust watering and light conditions.

Perennial Flax

Common Issues: Root rot, powdery mildew, aphids
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Powdery mildew: Improve air circulation and treat with fungicide. Aphids: Spray with insecticidal soap.

❓ Frequently Asked Questions — Comparing These Plants

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.

Perennial Flax

What are the light requirements for Perennial Flax?

Perennial Flax requires a minimum of six hours of direct sunlight per day to thrive and produce abundant blooms. A south-facing location is ideal, but east or west-facing exposures can also work if they provide sufficient sunlight. Insufficient light can lead to leggy growth, reduced flowering, and pale foliage. If growing indoors, place the plant near a sunny window or supplement with artificial grow lights. Rotate the plant regularly to ensure even light exposure on all sides. When transplanting, choose a location that receives full sun throughout the day. Be mindful of shadows cast by trees or buildings, especially during the shorter days of winter.

How do I care for Perennial Flax?

Perennial Flax thrives in full sun and well-drained soil. Water deeply but infrequently, allowing the soil to dry out between waterings. Amend heavy clay soils with compost or other organic matter to improve drainage. Fertilize lightly in spring with a balanced fertilizer to encourage blooming. Deadhead spent flowers to promote continued flowering. Cut back the plant after blooming to maintain its shape and encourage bushier growth. Provide support if necessary, as the stems can become leggy. Protect from excessive winter moisture in colder climates. Mulch around the base of the plant to retain moisture and suppress weeds. Monitor for pests and diseases, and treat promptly if necessary. Divide established plants every few years to rejuvenate them.

How do I propagate Perennial Flax?

Perennial Flax can be propagated by seed, division, or stem cuttings.

Last updated: April 28, 2026 — Plant care data reviewed and verified by our editorial team.