Fairy Moss vs Gunnera Plant Comparison

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

Fairy Moss

Fairy Moss

Azolla filiculoides

VS
Gunnera

Gunnera

Gunnera manicata

Fairy Moss

Fairy Moss

Azolla filiculoides

Azolla filiculoides, commonly known as Fairy Moss, is a small, free-floating aquatic fern. It forms a dense mat on the surface of still or slow-moving water. The plant is characterized by its tiny, overlapping leaves, which give it a moss-like appearance. It's typically grown outdoors in ponds, water gardens, or rice paddies. People cultivate it for its nitrogen-fixing abilities (symbiotic relationship with cyanobacteria), ornamental value, and potential use as a green manure or animal feed. It is not naturally an indoor plant and requires very specific conditions to thrive indoors.

Salviniaceae Americas (North and South)
✨ Features: Nitrogen fixation, potential as a biofertilizer, rapid growth.
📖 Read Complete Fairy Moss Guide
Gunnera

Gunnera

Gunnera manicata

Gunnera manicata, commonly known as Giant Rhubarb, is a massive, rhizomatous perennial plant prized for its enormous, textured leaves. Native to South America, it is primarily an outdoor plant, grown for its dramatic architectural presence in gardens and near water features. The leaves can reach impressive sizes, up to 2.5 meters across, creating a bold statement. While admired for its striking appearance, it is not suitable for indoor cultivation due to its size and specific environmental needs. It produces cone-shaped inflorescences of small reddish-green flowers in the summer.

Gunneraceae Southern Brazil, Colombia
✨ Features: Dramatic foliage, architectural presence
📖 Read Complete Gunnera Guide

Quick Plant Comparison

Feature Fairy Moss Gunnera
Light Full sun to partial shade Full sun to partial shade
Watering N/A - lives in water 2-3 times per week, depending on weather conditions
Humidity 70-90% 60-80%
Temperature 15-25°C 10-25°C
Care Level Expert Expert
Growth Rate Fast Fast
Max Height Less than 2.5 cm above the water surface. Not applicable for indoor growing. Outdoors: 2-3 meters
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil N/A - Free-floating, but benefits from nutrient-rich water. Rich, moisture-retentive soil with good drainage
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly (for thinning and water quality checks) 30 minutes weekly during the growing season

🔬 Botanical Information — Comparing These Plants

Fairy Moss

Scientific Name Azolla filiculoides
Family Salviniaceae
Native To Americas (North and South)
Also Known As Fairy Moss, Mosquito Fern, Water Fern
Leaves Tiny, overlapping leaves, typically 1-2 mm long. They are usually green, but can turn reddish in strong sunlight or under stress. The leaves are arranged in two rows along the stem.
Flowers Rarely flowers. When it does, the reproductive structures are small and inconspicuous, located at the base of the leaves.

Gunnera

Scientific Name Gunnera manicata
Family Gunneraceae
Native To Southern Brazil, Colombia
Also Known As Giant Rhubarb, Dinosaur Food
Leaves The leaves of Gunnera manicata are palmate, deeply lobed, and heavily textured with prominent veins. They are typically dark green and can reach up to 2.5 meters in diameter. The leaf stalks are thick and prickly.
Flowers Gunnera manicata produces cone-shaped inflorescences of small reddish-green flowers in the summer. The flowers are not particularly showy but add to the plant's overall architectural interest. It rarely flowers indoors.

📏 Size & Growth — Plant Comparison

Fairy Moss

Height Less than 2.5 cm above the water surface.
Spread Can spread rapidly to cover large areas of water surface.
Growth Rate Fast
Growth Pattern Free-floating aquatic fern that forms a dense mat on the water surface. It spreads rapidly through fragmentation.

Gunnera

Height Not applicable for indoor growing. Outdoors: 2-3 meters
Spread Spreads via rhizomes, can reach 4-5 meters wide
Growth Rate Fast
Growth Pattern Gunnera manicata grows from a large, rhizomatous base. It produces enormous leaves that unfurl from the center of the plant, creating a dense and spreading canopy. It is a vigorous grower and can quickly fill a large space.

🌱 Propagation — Comparing Plant Growth

Fairy Moss

Methods: Fragmentation (natural division of the plant)

Difficulty: Easy

Tips: Simply allow the plant to divide naturally. Ensure adequate nutrients and light for rapid growth.

Gunnera

Methods: Division, Seed

Difficulty: Moderate

Tips: Divide rhizomes in early spring or late fall. Sow seeds in spring after a period of cold stratification.

✨ Benefits & Features — Comparing Plant Value

Fairy Moss

Its symbiotic relationship with nitrogen-fixing cyanobacteria allows it to thrive in nutrient-poor waters. It can rapidly multiply, forming a dense mat on the water surface. Its small, overlapping leaves give it a unique moss-like appearance.

  • ✓ Natural nitrogen fixation for aquatic ecosystems.
  • ✓ Provides habitat and food for small aquatic organisms.
  • ✓ Aesthetically pleasing addition to water gardens.
  • ✓ Potential use as a sustainable fertilizer.
  • ✓ Can help suppress mosquito larvae by covering the water surface.
  • 🐾 Pet Safe

Gunnera

Gunnera manicata is unique due to its massive size and dramatic foliage, making it a standout architectural plant. Its leaves are among the largest of any herbaceous plant, creating a prehistoric and tropical aesthetic.

  • ✓ Adds a dramatic, architectural element to the garden.
  • ✓ Provides a focal point and visual interest.
  • ✓ Creates a lush, tropical atmosphere.
  • ✓ Attracts beneficial insects and pollinators.
  • ✓ Can be used to create shade and shelter for other plants.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Fairy Moss

Repotting N/A - No repotting needed as it is a free-floating plant.
Pruning Thinning out the mat may be necessary to prevent overcrowding.
Fertilizing Liquid aquatic plant fertilizer diluted to half strength, applied sparingly to the water every 2-4 weeks during the growing season.
Seasonal Care In winter, growth slows down. May need protection from freezing temperatures in colder climates. In summer, ensure adequate water levels and prevent overheating.

Gunnera

Repotting Not applicable for indoor growing. Outdoors: Divide every few years to control spread.
Pruning Remove dead or damaged leaves as needed. Cut back flower spikes after blooming.
Fertilizing Balanced slow-release fertilizer in spring, followed by liquid fertilizer every 4-6 weeks during the growing season
Seasonal Care In winter, protect the crown of the plant with a thick layer of mulch or its own dried leaves. In summer, ensure consistent moisture and provide shade during the hottest part of the day.

🌞 Light Requirements

Fairy Moss

Full sun to partial shade

Low light tolerant: ❌ No

Gunnera

Full sun to partial shade

Low light tolerant: ❌ No

💧 Watering Needs

Fairy Moss

Requires constantly moist conditions. It floats on water, so the surrounding water body needs to be maintained. Avoid letting the water dry out completely.

Gunnera

Requires consistently moist soil. Water deeply and regularly, especially during dry periods. Overwatering can lead to root rot, so ensure good drainage. Underwatering will cause the leaves to wilt and brown around the edges.

🌡️ Temperature & Humidity

Fairy Moss

Temperature: 15-25°C

Humidity: 70-90%

Gunnera

Temperature: 10-25°C

Humidity: 60-80%

🤔 Which Plant Is Right For You?

Fairy Moss

Fairy Moss

Azolla filiculoides
Care: Expert Time: 15 minutes weekly (for thinning and water quality checks) Beginner: No

Experienced aquatic gardeners looking to add a unique, nitrogen-fixing plant to their outdoor ponds or water features.

✅ Choose This Plant If...

  • You have an outdoor pond or water garden and want a natural way to fix nitrogen.
  • You are interested in using it as a green manure or animal feed.
  • You want a fast-growing plant to quickly cover the water surface.
  • You are looking for a unique and visually appealing aquatic plant.
  • You are interested in a plant with a symbiotic relationship with nitrogen-fixing bacteria.

❌ Skip This Plant If...

  • You do not have an outdoor pond or water garden.
  • You are looking for a low-maintenance indoor plant.
  • You live in a climate with harsh winters where it may not survive.
  • You are concerned about its potential to become invasive in certain environments.
📍 Ideal Location: Outdoor ponds, water gardens, or rice paddies.
🎨 Style: Naturalistic, Cottagecore, Wild Garden
🏠 Apartment Friendly: No
⚠️ According to available data, Azolla species are generally considered non-toxic to humans and animals. However, ingestion of large quantities may cause mild gastrointestinal upset due to the high fiber content.
Gunnera

Gunnera

Gunnera manicata
Care: Expert Time: 30 minutes weekly during the growing season Beginner: No

Gardeners with large properties and a desire for a dramatic, architectural plant.

✅ Choose This Plant If...

  • You have a large garden with a pond or stream.
  • You want a dramatic, architectural plant to make a statement.
  • You live in a region with mild, wet summers.
  • You are prepared to provide consistent moisture and protection from harsh weather.
  • You enjoy the challenge of growing unique and demanding plants.

❌ Skip This Plant If...

  • You have a small garden or limited space.
  • You are looking for an easy-to-care-for plant.
  • You live in a dry climate with limited water resources.
  • You have pets that might ingest the plant.
  • You want an indoor plant.
📍 Ideal Location: Not suitable for indoor growing. Outdoors: Near a pond or stream in a large garden.
🎨 Style: Tropical, Architectural, Dramatic
🏠 Apartment Friendly: No
⚠️ The ASPCA lists Gunnera species as containing oxalates, which can be toxic to dogs, cats, and horses. Symptoms include excessive salivation, vomiting, diarrhea, and loss of appetite. All parts of the plant are considered toxic.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Fairy Moss ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

🌿

Both plants have similar basic care requirements but differ in appearance and specific needs. Compare plants carefully to find the best fit for your space.

💡 Pro Tips For Comparing These Plants

Fairy Moss Care Tips

Fairy Moss is primarily an outdoor plant. Indoor cultivation is challenging due to the high light and humidity requirements. It needs a dedicated aquatic setup with strong lighting and consistent water quality. It can quickly take over a small container if conditions are ideal.

  • Provide adequate sunlight for optimal growth and nitrogen fixation.
  • Monitor water quality regularly and perform water changes as needed.
  • Thin out the mat periodically to prevent overcrowding.
  • Protect from freezing temperatures in winter.
  • Introduce beneficial insects to control pests.
❄️ Winter: In colder climates, Azolla may die back during the winter. It can survive as spores or small plant fragments in the sediment. Consider moving it indoors to a controlled environment if possible.
☀️ Summer: Ensure adequate water levels to prevent overheating. Provide some shade during the hottest part of the day to prevent scorching. Monitor for pests and diseases.

Gunnera Care Tips

Gunnera manicata is an outdoor plant that requires expert care due to its large size and specific environmental needs. It is not suitable for indoor cultivation. It needs ample space, consistent moisture, and protection from harsh weather conditions. Challenges include managing its aggressive growth and preventing root rot.

  • Provide consistent moisture, especially during dry periods.
  • Protect the crown of the plant in winter with a thick layer of mulch.
  • Fertilize regularly during the growing season.
  • Monitor for pests and diseases and treat promptly.
  • Provide shade during the hottest part of the day to prevent leaf scorch.
❄️ Winter: In winter, cut back the leaves and use them to cover the crown of the plant as insulation. Add a thick layer of mulch for extra protection in colder climates. Ensure the soil is well-drained to prevent root rot.
☀️ Summer: In summer, provide consistent moisture and shade during the hottest part of the day. Fertilize regularly to support vigorous growth. Monitor for pests and diseases and treat promptly.

⚠️ Common Problems & Solutions — Plant Care Comparison

Fairy Moss

Common Issues: Algae growth, nutrient deficiencies, pest infestations (e.g., aphids), water quality issues.
Solutions: Control algae with appropriate algaecides or by manually removing it. Address nutrient deficiencies with balanced aquatic plant fertilizer. Treat pests with insecticidal soap or by physically removing them. Maintain good water quality through regular water changes.

Gunnera

Common Issues: Root rot, Leaf scorch, Pests (slugs, snails)
Solutions: Ensure good drainage to prevent root rot. Provide shade during the hottest part of the day to prevent leaf scorch. Use slug and snail bait or handpick pests.

❓ Frequently Asked Questions — Comparing These Plants

Fairy Moss

What are the light requirements for Fairy Moss?

Fairy Moss requires bright, indirect light to flourish. Insufficient light will result in stunted growth and a loss of vibrant coloration. Place your Fairy Moss near a window that receives filtered sunlight, or use artificial lighting specifically designed for aquatic plants. LED grow lights are an excellent option, providing consistent and controlled light exposure.

How do I care for Fairy Moss?

Fairy Moss thrives in calm, nutrient-rich water. Provide bright, indirect light; direct sunlight can scorch the delicate fronds. Water temperature should be between 65-80°F (18-27°C). Maintain excellent water quality by performing regular water changes, especially if kept in a closed aquarium system.

How do I propagate Fairy Moss?

Fairy Moss is incredibly easy to propagate through division. Simply separate a portion of the existing colony and place it in a new container with suitable water conditions. The separated portion will quickly grow and expand, forming a new colony.

Gunnera

What are the light requirements for Gunnera?

Gunnera thrives in bright, indirect light. Direct sunlight can scorch its large leaves, leading to unsightly brown spots and stunted growth. An east-facing window is often ideal, providing gentle morning sun followed by ample shade throughout the day. If grown indoors, supplement with grow lights if natural light is insufficient. Avoid placing Gunnera in a dimly lit area, as this can result in leggy growth and smaller, less vibrant leaves. Rotate the plant regularly to ensure even light exposure on all sides. If growing outdoors, choose a location that receives partial shade, particularly during the hottest part of the day.

How do I care for Gunnera?

Gunnera demands consistent moisture and high humidity to thrive. Position in bright, indirect light, avoiding direct sunlight which can scorch the leaves. Water generously, ensuring the soil remains consistently damp but not waterlogged. A well-draining soil mix rich in organic matter is crucial. Fertilize regularly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Prune away dead or damaged leaves to encourage new growth and maintain plant health. Provide adequate space for the plant to grow, as it can reach significant sizes. Consider using a humidifier or pebble tray to increase humidity levels, especially indoors. Protect from frost and extreme temperatures. Regularly inspect for pests and diseases, addressing any issues promptly.

How do I propagate Gunnera?

Gunnera can be propagated through stem cuttings, division, or air layering. For stem cuttings, take a cutting from a healthy stem and root it in water or moist potting mix. For division, carefully separate the rhizome into smaller sections, ensuring each section has roots and leaves. Plant each section in its own pot. Air layering involves wrapping a section of stem with moist sphagnum moss and covering it with plastic wrap until roots develop. Once roots have formed, cut the stem below the roots and plant in its own pot. Maintain high humidity and consistent moisture during the propagation process. Spring and early summer are the best times for propagation. Ensure proper sanitation to prevent fungal infections.

Last updated: May 3, 2026 — Plant care data reviewed and verified by our editorial team.