Comfrey vs Flax Lily Plant Comparison

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

Comfrey

Comfrey

Symphytum officinale

VS
Flax Lily

Flax Lily

Dianella tasmanica

Comfrey

Comfrey

Symphytum officinale

Comfrey is a perennial herb known for its historical use in traditional medicine, though its internal use is now discouraged due to toxicity concerns. It features coarse, hairy leaves and bell-shaped flowers that are typically purple, blue, pink, or white. It grows outdoors to a height of about 1-3 feet and spreads via rhizomes. People grow it for its attractive foliage and flowers, and historically for its medicinal properties (though this is now largely avoided). It is primarily an outdoor plant and does not thrive indoors.

Boraginaceae Europe and Asia
✨ Features: Historically used in herbal medicine (though now discouraged), attracts pollinators.
📖 Read Complete Comfrey Guide
Flax Lily

Flax Lily

Dianella tasmanica

Dianella tasmanica, commonly known as the Flax Lily, is a rhizomatous perennial herb native to Tasmania. It features strappy, arching leaves that resemble flax, hence the name. It typically grows outdoors in shaded or partially shaded areas. While it can be grown indoors, it requires specific conditions to thrive and may not flower as readily as when grown outdoors. People grow it for its attractive foliage, clumping habit, and relatively low maintenance when grown in suitable conditions.

Asphodelaceae Tasmania, Australia
✨ Features: Attractive foliage, clumping habit
📖 Read Complete Flax Lily Guide

Quick Plant Comparison

Feature Comfrey Flax Lily
Light Full sun to partial shade Bright, indirect light. Avoid direct sunlight, especially during the hottest part of the day.
Watering Every 1-2 weeks, depending on weather and soil drainage Every 1-2 weeks, depending on environmental conditions and pot size.
Humidity 30-50% 40-60%
Temperature 10-25°C 15-24°C
Care Level Expert Moderate
Growth Rate Fast Moderate
Max Height N/A - Not suitable for indoor growing 0.5-1 meter (indoors, typically smaller)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-drained soil, loamy or sandy soil is best. Tolerates a wide range of soil types, including poor soil. Well-draining potting mix with added perlite or sand.
Beginner Friendly ❌ No With Caution
Weekly Maintenance 10 minutes weekly (mostly weeding and watering) 10 minutes weekly

🔬 Botanical Information — Comparing These Plants

Comfrey

Scientific Name Symphytum officinale
Family Boraginaceae
Native To Europe and Asia
Also Known As Comfrey, Common Comfrey, Knitbone, Boneset
Leaves The leaves are large, coarse, and hairy, with an oval to lanceolate shape. They are typically dark green and can grow up to 10 inches long. The texture is rough due to the presence of bristly hairs.
Flowers Comfrey produces bell-shaped flowers that hang in clusters. The flowers are typically purple, blue, pink, or white. It rarely flowers indoors.

Flax Lily

Scientific Name Dianella tasmanica
Family Asphodelaceae
Native To Tasmania, Australia
Also Known As Flax Lily, Tasman Flax Lily
Leaves The leaves are long, linear, and strap-like, typically 30-90 cm long and 1-3 cm wide. They are usually green, but some cultivars have variegated foliage with stripes of yellow or white. The texture is smooth and slightly glossy.
Flowers It may flower indoors, but it is more common when grown outdoors. The flowers are small, star-shaped, and blue or purple, followed by blue or purple berries.

📏 Size & Growth — Plant Comparison

Comfrey

Height N/A - Not suitable for indoor growing
Spread N/A - Not suitable for indoor growing
Growth Rate Fast
Growth Pattern Comfrey grows as an upright, bushy perennial. It spreads aggressively via rhizomes, forming dense clumps.

Flax Lily

Height 0.5-1 meter (indoors, typically smaller)
Spread 0.5-1 meter (spreads via rhizomes)
Growth Rate Moderate
Growth Pattern It grows in a clumping habit, with leaves arching outwards from the base. It spreads via rhizomes, gradually expanding its footprint.

🌱 Propagation — Comparing Plant Growth

Comfrey

Methods: Root cuttings, Division, Seed

Difficulty: Easy

Tips: Divide established plants in spring or fall. Root cuttings should be taken in late fall or early spring. Sow seeds directly in the garden in spring or fall.

Flax Lily

Methods: Division, Seed

Difficulty: Easy

Tips: Divide rhizomes in spring or early summer. Ensure each division has healthy roots and leaves. Sow seeds in spring after soaking them in warm water for 24 hours.

✨ Benefits & Features — Comparing Plant Value

Comfrey

Comfrey is known for its rapid growth and ability to accumulate nutrients from the soil. It's also notable for its historical use in traditional medicine, although this is now largely discouraged due to toxicity concerns.

  • ✓ Attracts pollinators
  • ✓ Provides ground cover
  • ✓ Tolerates poor soil
  • ✓ Low maintenance
  • ✓ Historically used in herbal medicine
  • ⚠️ Toxic to pets

Flax Lily

Its strappy, arching leaves give it a unique texture and appearance. It spreads via rhizomes, forming clumps over time. While it can be grown indoors, it is primarily an outdoor plant.

  • ✓ Adds a touch of greenery to indoor spaces.
  • ✓ Relatively low maintenance.
  • ✓ Can be easily propagated.
  • ✓ Provides a calming, natural aesthetic.
  • ✓ Tolerates some neglect.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Comfrey

Repotting N/A - Not suitable for indoor growing
Pruning Cut back foliage after flowering to encourage new growth. Remove any dead or damaged leaves.
Fertilizing Apply a balanced fertilizer (10-10-10) in early spring. Avoid over-fertilizing, as this can reduce flowering.
Seasonal Care In spring, apply fertilizer and divide plants if needed. In summer, water regularly and monitor for pests and diseases. In fall, cut back foliage after flowering. In winter, the plant will die back to the ground.

Flax Lily

Repotting Every 1-2 years, or when the plant becomes root-bound. Divide the rhizomes during repotting to control spread.
Pruning Remove dead or damaged leaves as needed. Trim back excessive growth to maintain shape.
Fertilizing Balanced liquid fertilizer diluted to half strength, every 2-3 months during the growing season (spring and summer).
Seasonal Care Reduce watering in winter when growth slows. Provide adequate light during shorter days. In summer, ensure adequate moisture and protect from intense direct sunlight.

🌞 Light Requirements

Comfrey

Full sun to partial shade

Low light tolerant: ❌ No

Flax Lily

Bright, indirect light. Avoid direct sunlight, especially during the hottest part of the day.

Low light tolerant: ❌ No

💧 Watering Needs

Comfrey

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Comfrey prefers consistently moist soil but doesn't like to sit in standing water. Signs of underwatering include wilting leaves; overwatering signs include yellowing leaves and a musty smell.

Flax Lily

Water thoroughly when the top inch of soil feels dry to the touch. Ensure good drainage to prevent root rot. Overwatering can lead to yellowing leaves and root rot, while underwatering can cause the leaves to droop and brown at the tips.

🌡️ Temperature & Humidity

Comfrey

Temperature: 10-25°C

Humidity: 30-50%

Flax Lily

Temperature: 15-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Comfrey

Comfrey

Symphytum officinale
Care: Expert Time: 10 minutes weekly (mostly weeding and watering) Beginner: No

Experienced gardeners looking for a low-maintenance, fast-growing ground cover in a large outdoor space, understanding the toxicity risks.

✅ Choose This Plant If...

  • You have a large outdoor space and need a fast-growing ground cover.
  • You are interested in attracting pollinators to your garden.
  • You are an experienced gardener familiar with the plant's toxicity.
  • You want a low-maintenance plant that can tolerate a wide range of soil conditions.
  • You appreciate plants with a rich history of traditional use (though not for internal consumption).

❌ Skip This Plant If...

  • You have pets or small children who might ingest the plant.
  • You have limited space, as comfrey spreads aggressively.
  • You are looking for an easy-to-grow indoor plant.
📍 Ideal Location: Outdoor garden or meadow with full sun to partial shade.
🎨 Style: Cottage garden, Naturalistic
🏠 Apartment Friendly: No
⚠️ Comfrey contains pyrrolizidine alkaloids (PAs), which are toxic to dogs, cats, and horses. Symptoms include liver damage, vomiting, diarrhea, and abdominal pain. All parts of the plant are toxic, but the roots contain the highest concentration of PAs.
Flax Lily

Flax Lily

Dianella tasmanica
Care: Moderate Time: 10 minutes weekly Beginner: With-caution

Someone looking for a low-maintenance plant with attractive foliage, but who is aware of its toxicity to pets.

✅ Choose This Plant If...

  • You want a plant with attractive, grass-like foliage.
  • You have a location with bright, indirect light.
  • You are looking for a relatively low-maintenance plant.
  • You want a plant that can be easily propagated by division.
  • You understand its toxicity to pets and can keep it out of their reach.

❌ Skip This Plant If...

  • You have pets that may ingest plants.
  • You have a very dark home with limited natural light.
  • You are prone to overwatering plants.
📍 Ideal Location: Bright bathroom, living room near a window with filtered light, or a covered patio.
🎨 Style: Modern, Tropical, Bohemian
🏠 Apartment Friendly: Yes
⚠️ According to the ASPCA, Dianella species are toxic to dogs, cats, and horses. The toxic principle is not explicitly stated, but symptoms include vomiting and diarrhea.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Neither - caution
Less Maintenance Similar effort
Apartment Friendly Flax Lily

⚡ Key Differences Between These Plants

🎯

Comfrey is rated Expert care level, while Flax Lily is Moderate.

📈

Comfrey has fast growth, while Flax Lily grows moderate.

💡 Pro Tips For Comparing These Plants

Comfrey Care Tips

Comfrey is an outdoor plant that is very difficult to grow indoors due to its need for full sun and its aggressive growth habit. It spreads via rhizomes and requires a large space to thrive. Indoor cultivation is not recommended due to these challenges and the plant's toxicity.

  • Plant in a location where it can spread freely.
  • Water deeply but infrequently.
  • Avoid over-fertilizing.
  • Monitor for pests and diseases.
  • Be aware of the plant's toxicity and take precautions to prevent ingestion.
❄️ Winter: Comfrey is dormant in winter. Cut back foliage after it dies back. No watering or fertilizing is needed.
☀️ Summer: Water regularly during dry periods. Monitor for pests and diseases. Provide shade during the hottest part of the day in very hot climates.

Flax Lily Care Tips

Flax Lily is relatively easy to care for, but requires bright, indirect light and well-draining soil. Overwatering is a common problem. It may not flower indoors as readily as outdoors. It spreads via rhizomes, so repotting may be needed more frequently than other houseplants.

  • Allow the top inch of soil to dry out before watering.
  • Provide bright, indirect light to maintain vibrant foliage.
  • Fertilize sparingly during the growing season.
  • Monitor for pests like spider mites and treat promptly.
  • Repot every 1-2 years to prevent root-bound conditions.
❄️ Winter: Reduce watering frequency during winter as growth slows down. Ensure the plant still receives adequate light. Avoid placing it near cold drafts.
☀️ Summer: Provide adequate moisture during the warmer months. Protect from intense direct sunlight to prevent leaf burn. Increase humidity if possible.

⚠️ Common Problems & Solutions — Plant Care Comparison

Comfrey

Common Issues: Powdery mildew, Rust, Slugs and snails
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. | Rust: Remove infected leaves and apply a fungicide. | Slugs and snails: Use slug bait or handpick them off the plants.

Flax Lily

Common Issues: Root rot, brown leaf tips, spider mites
Solutions: Root rot: Ensure proper drainage and avoid overwatering. Treat with fungicide if necessary.|Brown leaf tips: Increase humidity or water more consistently. Avoid letting the soil dry out completely.|Spider mites: Treat with insecticidal soap or neem oil.

❓ Frequently Asked Questions — Comparing These Plants

Comfrey

What are the light requirements for Comfrey?

Comfrey thrives in partial to full sunlight, requiring at least 4-6 hours of direct sunlight per day for optimal growth and flowering. However, it can also tolerate partial shade, especially in hotter climates where intense afternoon sun can scorch its leaves. When grown in full sun, ensure adequate watering to prevent the soil from drying out.

How do I care for Comfrey?

Comfrey is relatively easy to care for. Plant in a location with partial to full sunlight, although it tolerates shade. Soil should be well-draining and fertile, but Comfrey is adaptable to various soil types. Water regularly, especially during dry periods, keeping the soil consistently moist but not waterlogged. Fertilize in spring with a balanced fertilizer to promote healthy growth and flowering.

How do I propagate Comfrey?

Comfrey is easily propagated through division, stem cuttings, or root cuttings.

Flax Lily

What are the light requirements for Flax Lily?

Flax Lily flourishes in bright, indirect light. Direct sunlight can scorch its leaves, so avoid placing it in south-facing windows without some form of shading. An east or west-facing window is ideal, where it can receive gentle morning or afternoon light. If your plant is in a lower-light environment, its growth may be slower, and the colors may appear less vibrant. Rotate your plant regularly to ensure even light exposure on all sides. Insufficient light can lead to leggy growth and faded foliage.

How do I care for Flax Lily?

Flax Lily thrives in bright, indirect light but can tolerate lower light conditions. Water when the top inch of soil feels dry, ensuring the pot has good drainage to prevent root rot. Maintain moderate humidity levels, especially during dry seasons, by misting the plant regularly or using a humidifier. Fertilize monthly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Repot every 1-2 years, or when the plant becomes root-bound, using a well-draining potting mix. Prune away any dead or yellowing leaves to maintain its appearance and health. Protect from frost and extreme temperatures. Proper watering, light, and humidity are key to a thriving Flax Lily.

How do I propagate Flax Lily?

Flax Lily can be propagated through division, stem cuttings, and air layering.

Last updated: April 27, 2026 — Plant care data reviewed and verified by our editorial team.