Flax Lily vs Oat Grass Plant Comparison

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

Flax Lily

Flax Lily

Dianella tasmanica

VS
Oat Grass

Oat Grass

Avena sativa

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
Oat Grass

Oat Grass

Avena sativa

Avena sativa, or oat grass, is an annual cereal grain. It's characterized by its slender, upright stems and long, narrow leaves. Primarily grown outdoors for grain production, it's also cultivated as a cover crop and animal fodder. While sometimes grown indoors for pets, it's not naturally an indoor plant and requires specific conditions to thrive. People grow it for its nutritional value, as a pet treat, or for its aesthetic appeal as a temporary green addition.

Poaceae Likely originated in the Near East, now cultivated worldwide.
✨ Features: Provides a source of fiber and nutrients for pets.
📖 Read Complete Oat Grass Guide

Quick Plant Comparison

Feature Flax Lily Oat Grass
Light Bright, indirect light. Avoid direct sunlight, especially during the hottest part of the day. Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth.
Watering Every 1-2 weeks, depending on environmental conditions and pot size. Every 3-7 days, depending on environmental conditions and pot size.
Humidity 40-60% 40-60%
Temperature 15-24°C 15-24°C
Care Level Moderate Expert
Growth Rate Moderate Fast
Max Height 0.5-1 meter (indoors, typically smaller) 0.3-1 meter (indoors, typically shorter)
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining potting mix with added perlite or sand. Well-draining potting mix or garden soil.
Beginner Friendly With Caution With Caution
Weekly Maintenance 10 minutes weekly 5-10 minutes weekly.

🔬 Botanical Information — Comparing These Plants

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.

Oat Grass

Scientific Name Avena sativa
Family Poaceae
Native To Likely originated in the Near East, now cultivated worldwide.
Also Known As Oat, Common Oat
Leaves Long, narrow, and flat leaves, typically green in color. They have a smooth texture and parallel veins.
Flowers Rarely flowers indoors. Outdoors, it produces panicles of small, drooping spikelets containing the oat grains.

📏 Size & Growth — Plant Comparison

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.

Oat Grass

Height 0.3-1 meter (indoors, typically shorter)
Spread 0.15-0.3 meters
Growth Rate Fast
Growth Pattern Upright, clumping grass with slender stems and long, narrow leaves. It grows rapidly from seed to maturity.

🌱 Propagation — Comparing Plant Growth

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.

Oat Grass

Methods: Seed

Difficulty: Easy

Tips: Sow seeds directly into soil, keep moist, and provide adequate sunlight.

✨ Benefits & Features — Comparing Plant Value

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

Oat Grass

Oat grass is a fast-growing annual that provides a fresh, green aesthetic. Its primary use is as a food source, making it a practical and visually appealing plant.

  • ✓ Provides a natural and healthy treat for pets.
  • ✓ Adds a touch of greenery to indoor spaces.
  • ✓ Easy to grow from seed.
  • ✓ Non-toxic and safe for households with pets and children.
  • ✓ Can be used as a temporary green filler in arrangements.
  • 🐾 Pet Safe

📅 Maintenance Schedule — Plant Care Comparison

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.

Oat Grass

Repotting Not typically repotted as it's an annual. If grown in a container, refresh the soil annually.
Pruning Trim dead or yellowing leaves to maintain appearance.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, applied every 4-6 weeks during the growing season.
Seasonal Care In winter, reduce watering frequency. In summer, ensure adequate sunlight and ventilation.

🌞 Light Requirements

Flax Lily

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

Low light tolerant: ❌ No

Oat Grass

Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth.

Low light tolerant: ❌ No

💧 Watering Needs

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.

Oat Grass

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Signs of underwatering include wilting and browning leaf tips. Overwatering can cause yellowing leaves and a soggy soil surface.

🌡️ Temperature & Humidity

Flax Lily

Temperature: 15-24°C

Humidity: 40-60%

Oat Grass

Temperature: 15-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

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.
Oat Grass

Oat Grass

Avena sativa
Care: Expert Time: 5-10 minutes weekly. Beginner: With-caution

Pet owners who want to provide a safe and natural treat for their animals.

✅ Choose This Plant If...

  • You want to provide a safe and natural treat for your pets.
  • You enjoy the aesthetic of fresh greenery in your home, even temporarily.
  • You want a fast-growing plant from seed.
  • You are looking for a non-toxic plant option.
  • You want to try growing your own pet food.

❌ Skip This Plant If...

  • You cannot provide at least 6 hours of direct sunlight daily.
  • You are looking for a long-term indoor plant.
  • You are prone to overwatering plants.
📍 Ideal Location: Sunny windowsill or balcony.
🎨 Style: Natural, Rustic, Farmhouse
🏠 Apartment Friendly: Limited
⚠️ Avena sativa is generally considered non-toxic to humans, dogs, cats, and horses. However, large quantities may cause digestive upset.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Oat Grass ✓
Less Maintenance Similar effort
Apartment Friendly Flax Lily

⚡ Key Differences Between These Plants

🎯

Flax Lily is rated Moderate care level, while Oat Grass is Expert.

📈

Flax Lily has moderate growth, while Oat Grass grows fast.

💡 Pro Tips For Comparing These Plants

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.

Oat Grass Care Tips

Oat grass is primarily an outdoor plant. Growing it indoors requires ample sunlight, proper watering, and good ventilation. It's best suited as a temporary indoor plant, as it may not thrive long-term without ideal outdoor conditions. Expect a shorter lifespan indoors.

  • Ensure excellent drainage to prevent root rot.
  • Provide supplemental lighting if natural sunlight is insufficient.
  • Rotate the pot regularly to ensure even growth.
  • Avoid overcrowding the seeds when planting.
  • Monitor for pests and diseases regularly.
❄️ Winter: Reduce watering frequency during winter months. Ensure adequate light if grown indoors.
☀️ Summer: Provide adequate ventilation and ensure the soil doesn't dry out too quickly in hot weather.

⚠️ Common Problems & Solutions — Plant Care Comparison

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.

Oat Grass

Common Issues: Yellowing leaves, fungal diseases, pest infestations (aphids).
Solutions: Yellowing leaves: Adjust watering and ensure proper drainage. Fungal diseases: Improve ventilation and use a fungicide. Pest infestations: Treat with insecticidal soap.

❓ Frequently Asked Questions — Comparing These Plants

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.

Oat Grass

What are the light requirements for Oat Grass?

Oat Grass flourishes in bright, indirect light. Insufficient light can lead to leggy growth and reduced flowering. An east-facing window is often ideal, providing gentle morning sun. A west-facing window can also work, but be cautious of intense afternoon sun, which can scorch the leaves. If you only have south-facing windows, filter the light with a sheer curtain.

How do I care for Oat Grass?

Oat Grass thrives in bright, indirect light. Direct sunlight can scorch its leaves. Water thoroughly when the top inch of soil feels dry to the touch, ensuring good drainage to prevent root rot. Use a well-draining potting mix. Fertilize monthly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Maintain a moderate humidity level, ideally between 40-60%.

How do I propagate Oat Grass?

Oat Grass can be propagated by division. In spring, carefully remove the plant from its pot and gently separate the root ball into smaller clumps, ensuring each clump has healthy roots and foliage. Replant each clump in its own pot with fresh, well-draining potting mix. Water thoroughly and keep in a bright, indirect light location.

Last updated: April 29, 2026 — Plant care data reviewed and verified by our editorial team.