Asarum vs Fairy Moss Plant Comparison

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

Asarum

Asarum

Asarum canadense

VS
Fairy Moss

Fairy Moss

Azolla filiculoides

Asarum

Asarum

Asarum canadense

Asarum canadense, or Canadian Wild Ginger, is a rhizomatous herbaceous perennial typically found in moist, deciduous woodlands. It's known for its kidney-shaped to heart-shaped, velvety green leaves that grow in pairs from creeping rhizomes. The plant produces a single, bell-shaped, brownish-purple flower near the ground in spring, often hidden beneath the foliage. While called 'ginger', it's not related to culinary ginger and should not be consumed as a substitute. It is primarily grown as a groundcover in shaded gardens for its attractive foliage and ability to suppress weeds. It is NOT suited for indoor growing.

Aristolochiaceae Eastern North America
✨ Features: Attractive foliage, effective groundcover, deer resistant.
📖 Read Complete Asarum Guide
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

Quick Plant Comparison

Feature Asarum Fairy Moss
Light Full to partial shade. Cannot tolerate direct sunlight. Full sun to partial shade
Watering Every 3-7 days, depending on weather and soil drainage. N/A - lives in water
Humidity 50-70% 70-90%
Temperature 10-24°C 15-25°C
Care Level Expert Expert
Growth Rate Moderate Fast
Max Height 0.15-0.3 meters (outdoors) Less than 2.5 cm above the water surface.
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Rich, well-draining soil with plenty of organic matter. A mix of compost, leaf mold, and garden soil is ideal. N/A - Free-floating, but benefits from nutrient-rich water.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 10 minutes weekly (weeding, watering) 15 minutes weekly (for thinning and water quality checks)

🔬 Botanical Information — Comparing These Plants

Asarum

Scientific Name Asarum canadense
Family Aristolochiaceae
Native To Eastern North America
Also Known As Canadian Wild Ginger, Broad-leaved Asarum, Indian Ginger
Leaves The leaves are kidney-shaped to heart-shaped, typically 10-20 cm wide, with a velvety texture and a deep green color. They have prominent veins and a slightly ruffled edge.
Flowers The plant produces a single, bell-shaped flower near the ground in spring. The flower is typically brownish-purple and often hidden beneath the foliage. It rarely flowers indoors.

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.

📏 Size & Growth — Plant Comparison

Asarum

Height 0.15-0.3 meters (outdoors)
Spread Spreads indefinitely via rhizomes (outdoors)
Growth Rate Moderate
Growth Pattern Spreads horizontally via rhizomes, forming a dense groundcover. The leaves emerge in pairs from the rhizomes.

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.

🌱 Propagation — Comparing Plant Growth

Asarum

Methods: Division, Seed

Difficulty: Moderate

Tips: Divide rhizomes in early spring or fall. Sow seeds in fall for germination the following spring. Ensure good drainage and consistent moisture.

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.

✨ Benefits & Features — Comparing Plant Value

Asarum

The plant's unique bell-shaped flowers are often hidden beneath the foliage. It is also known for its ginger-like aroma when the rhizomes are crushed, despite not being related to true ginger.

  • ✓ Provides groundcover in shady areas
  • ✓ Attracts pollinators
  • ✓ Deer resistant
  • ✓ Erosion control on slopes
  • ✓ Adds visual interest with unique foliage
  • ⚠️ Toxic to pets

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

📅 Maintenance Schedule — Plant Care Comparison

Asarum

Repotting Not applicable for outdoor groundcover. If attempting indoors, repot annually in spring to accommodate rhizome growth.
Pruning Remove dead or damaged foliage as needed.
Fertilizing Apply a balanced, slow-release fertilizer in early spring. Avoid over-fertilizing.
Seasonal Care In spring, apply fertilizer and remove any dead foliage. In summer, ensure adequate moisture during dry spells. In fall, divide rhizomes if desired. In winter, the foliage dies back, and the plant goes dormant.

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.

🌞 Light Requirements

Asarum

Full to partial shade. Cannot tolerate direct sunlight.

Low light tolerant: ❌ No

Fairy Moss

Full sun to partial shade

Low light tolerant: ❌ No

💧 Watering Needs

Asarum

Keep soil consistently moist, but not waterlogged. Water when the top inch of soil feels dry. Overwatering can lead to root rot, while underwatering will cause the leaves to wilt and brown.

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.

🌡️ Temperature & Humidity

Asarum

Temperature: 10-24°C

Humidity: 50-70%

Fairy Moss

Temperature: 15-25°C

Humidity: 70-90%

🤔 Which Plant Is Right For You?

Asarum

Asarum

Asarum canadense
Care: Expert Time: 10 minutes weekly (weeding, watering) Beginner: No

Gardeners looking for a shade-loving groundcover in woodland settings.

✅ Choose This Plant If...

  • You have a shady woodland garden and need a groundcover
  • You want a deer-resistant plant
  • You appreciate unique foliage textures
  • You want to attract pollinators to your garden (though flowers are hidden)
  • You are looking for a native plant to support local ecosystems.

❌ Skip This Plant If...

  • You have pets that might ingest the plant
  • You do not have a suitable outdoor location with shade and moist soil
  • You are looking for a low-maintenance indoor plant.
📍 Ideal Location: Shady woodland garden or shaded area under trees.
🎨 Style: Woodland, Naturalistic, Cottage
🏠 Apartment Friendly: No
⚠️ Contains aristolochic acids, which are toxic to dogs, cats, and horses. Symptoms include vomiting, diarrhea, and kidney damage. All parts of the plant are considered toxic.
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.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

📈

Asarum has moderate growth, while Fairy Moss grows fast.

💡 Pro Tips For Comparing These Plants

Asarum Care Tips

Asarum canadense is primarily an outdoor plant and is very difficult to grow indoors. It requires specific shade and moisture conditions that are hard to replicate indoors. It also spreads via rhizomes, which would quickly outgrow a container. Toxicity to pets is a major concern.

  • Ensure excellent drainage to prevent root rot
  • Provide consistent moisture, especially during dry periods
  • Apply a layer of mulch to retain moisture and suppress weeds
  • Divide rhizomes every few years to prevent overcrowding
  • Monitor for slugs and snails and take appropriate action
❄️ Winter: The foliage dies back in winter, and the plant goes dormant. A layer of mulch can help protect the rhizomes from extreme cold.
☀️ Summer: Ensure adequate moisture during dry spells. Provide shade to protect the leaves from scorching.

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.

⚠️ Common Problems & Solutions — Plant Care Comparison

Asarum

Common Issues: Root rot, slugs and snails, leaf spot
Solutions: Ensure good drainage to prevent root rot. Use slug and snail bait or handpick them off the plants. Apply a fungicide for leaf spot.

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.

❓ Frequently Asked Questions — Comparing These Plants

Asarum

What are the light requirements for Asarum?

Asarum requires shade to partial shade. Direct sunlight can scorch its delicate leaves, leading to browning and stunted growth. Ideal placement is under the canopy of trees or on the north side of a building, where it receives filtered sunlight or dappled shade. Avoid locations that receive intense afternoon sun. If growing Asarum indoors, place it near a north-facing window or use sheer curtains to diffuse the light. Insufficient light can result in leggy growth and reduced flowering. Observe the plant’s foliage for signs of stress, such as pale or yellowing leaves, and adjust the light accordingly. Remember that the intensity of light changes throughout the year, so monitor your Asarum’s light exposure and adjust its placement as needed.

How do I care for Asarum?

Asarum thrives in shady locations with well-draining, humus-rich soil. Water regularly, especially during dry periods, keeping the soil consistently moist but not waterlogged. Fertilize sparingly in early spring with a balanced, slow-release fertilizer to encourage healthy growth and blooming. Avoid direct sunlight, which can scorch the leaves. Mulch around the plants to retain moisture and suppress weeds. Prune away any dead or damaged foliage to maintain appearance and prevent disease. Asarum prefers cool temperatures and high humidity. Provide good air circulation to prevent fungal diseases. Repot container-grown plants every few years in spring. Monitor for pests such as slugs and snails and treat accordingly. With proper care, Asarum will reward you with its beautiful foliage and unique flowers.

How do I propagate Asarum?

Asarum is best propagated by division in early spring or fall. Carefully dig up the plant and divide the rhizomes into sections, ensuring each section has roots and foliage. Replant the divisions in well-draining, humus-rich soil. Keep the soil consistently moist until the plants are established. Stem cuttings are not a reliable method for Asarum propagation. Keiki, or plantlets, do not naturally form on Asarum. Division is the most successful method for propagating this plant. Ensure the divisions are planted at the same depth as the original plant. Mulch around the newly planted divisions to retain moisture and suppress weeds. Water thoroughly after planting.

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.

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