Fairy Moss vs Lemongrass 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
Lemongrass

Lemongrass

Cymbopogon citratus

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
Lemongrass

Lemongrass

Cymbopogon citratus

Lemongrass is a tall, perennial grass characterized by its fragrant, lemon-scented leaves and stalks. It typically grows in dense clumps, reaching heights of 3-5 feet outdoors. The plant is primarily grown for its culinary and medicinal uses, as well as its aromatic properties. While it can be grown indoors, it requires very bright light and consistent care to thrive. It is more commonly cultivated outdoors in warmer climates.

Poaceae Southeast Asia (India, Sri Lanka, Malaysia, Thailand)
✨ Features: Aromatic leaves, culinary uses, insect repellent properties (citronella oil)
📖 Read Complete Lemongrass Guide

Quick Plant Comparison

Feature Fairy Moss Lemongrass
Light Full sun to partial shade Full sun (6-8 hours of direct sunlight daily)
Watering N/A - lives in water Every 3-7 days, depending on environmental conditions and pot size. More frequent watering is needed during hot, sunny periods.
Humidity 70-90% 40-60%
Temperature 15-25°C 18-30°C
Care Level Expert Expert
Growth Rate Fast Fast
Max Height Less than 2.5 cm above the water surface. 1-3 feet (indoors), 3-5 feet (outdoors)
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil N/A - Free-floating, but benefits from nutrient-rich water. Well-draining, loamy soil. A mix of potting soil, perlite, and sand is suitable.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly (for thinning and water quality checks) 15 minutes weekly

🔬 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.

Lemongrass

Scientific Name Cymbopogon citratus
Family Poaceae
Native To Southeast Asia (India, Sri Lanka, Malaysia, Thailand)
Also Known As Lemongrass, Oil Grass, Fever Grass, Citronella Grass
Leaves The leaves are long, slender, and blade-like, typically 1-3 feet long and 0.5-1 inch wide. They are bright green in color and have a rough texture. The leaves emit a strong lemon scent when crushed.
Flowers Lemongrass rarely flowers indoors. Outdoors, it may produce flower spikes with small, inconspicuous flowers under ideal conditions, but flowering is not its primary feature.

📏 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.

Lemongrass

Height 1-3 feet (indoors), 3-5 feet (outdoors)
Spread 1-2 feet, spreads via rhizomes
Growth Rate Fast
Growth Pattern Lemongrass grows in dense clumps, with upright stalks and arching leaves. It spreads via rhizomes, which can lead to aggressive growth if not contained.

🌱 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.

Lemongrass

Methods: Division, Seed, Rooting stem cuttings in water

Difficulty: Easy

Tips: Divide mature clumps in spring or summer. For stem cuttings, place the cut end in water until roots develop, then plant in soil. Keep soil consistently moist during propagation.

✨ 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

Lemongrass

Lemongrass is distinguished by its strong lemon scent and flavor, which is due to the presence of citronella oil. It is a fast-growing grass that can reach impressive heights in optimal conditions. Its culinary and medicinal uses make it a valuable addition to any garden.

  • ✓ Fresh lemongrass for culinary use
  • ✓ Natural insect repellent
  • ✓ Aromatic fragrance
  • ✓ Adds a tropical aesthetic to your garden or home
  • ✓ Potential medicinal benefits (consult a healthcare professional)
  • ⚠️ 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.

Lemongrass

Repotting Every 1-2 years, or when the plant becomes root-bound. Divide the plant during repotting to control its size.
Pruning Regularly trim dead or yellowing leaves. Cut back the plant in late winter or early spring to encourage new growth.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-4 weeks during the growing season (spring and summer).
Seasonal Care During the growing season (spring/summer), water and fertilize regularly. In winter, reduce watering and provide adequate light. Protect from frost if grown outdoors.

🌞 Light Requirements

Fairy Moss

Full sun to partial shade

Low light tolerant: ❌ No

Lemongrass

Full sun (6-8 hours of direct sunlight daily)

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.

Lemongrass

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. Signs of overwatering include yellowing leaves and a soggy soil.

🌡️ Temperature & Humidity

Fairy Moss

Temperature: 15-25°C

Humidity: 70-90%

Lemongrass

Temperature: 18-30°C

Humidity: 40-60%

🤔 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.
Lemongrass

Lemongrass

Cymbopogon citratus
Care: Expert Time: 15 minutes weekly Beginner: No

Experienced gardeners in warm climates who want to grow their own culinary herb and are aware of the plant's toxicity to pets.

✅ Choose This Plant If...

  • You want to grow your own fresh lemongrass for cooking and teas.
  • You live in a warm climate with plenty of sunlight.
  • You are an experienced gardener looking for a rewarding challenge.
  • You want a natural insect repellent in your garden.
  • You are aware of the plant's toxicity to pets and can keep it out of their reach.

❌ Skip This Plant If...

  • You have pets that may ingest the plant.
  • You live in a cold climate with limited sunlight.
  • You are a beginner gardener looking for an easy-care plant.
📍 Ideal Location: Outdoors in a sunny garden bed or large container. Indoors, a south-facing window with supplemental lighting.
🎨 Style: Tropical, Bohemian, Natural
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, lemongrass is toxic to dogs, cats, and horses. Symptoms include vomiting, diarrhea, and abdominal pain. The leaves and stems are the toxic parts.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

☀️

Fairy Moss needs full sun to partial shade, while Lemongrass prefers full sun (6-8 hours of direct sunlight daily).

💡 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.

Lemongrass Care Tips

Lemongrass is relatively easy to grow outdoors in warm climates with ample sunlight. Indoor cultivation is challenging due to high light requirements. It needs regular watering, fertilization, and repotting due to its fast growth and rhizomatous nature. Toxicity to pets is a major concern.

  • Provide at least 6 hours of direct sunlight daily.
  • Water deeply when the top inch of soil is dry.
  • Fertilize regularly during the growing season.
  • Protect from frost in colder climates.
  • Divide the plant every 1-2 years to prevent overcrowding.
❄️ Winter: Reduce watering frequency during winter. If grown outdoors in a cold climate, protect the plant from frost by bringing it indoors or covering it with a frost blanket. Ensure adequate light if kept indoors.
☀️ Summer: Water more frequently during hot summer months. Provide afternoon shade in extremely hot climates to prevent leaf burn. Fertilize regularly to support growth.

⚠️ 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.

Lemongrass

Common Issues: Root rot, spider mites, insufficient sunlight, browning leaf tips
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Spider mites: Treat with insecticidal soap or neem oil. Insufficient sunlight: Provide supplemental lighting or move to a sunnier location. Browning leaf tips: Increase humidity and ensure consistent watering.

❓ 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.

Lemongrass

What are the light requirements for Lemongrass?

Lemongrass demands bright, indirect sunlight for optimal growth. Insufficient light can lead to leggy growth and reduced essential oil production, diminishing its characteristic aroma. A south- or east-facing window is ideal, providing ample light without direct scorching. If direct sunlight is unavoidable, filter it with a sheer curtain. Rotate the plant regularly to ensure even light exposure on all sides. If natural light is inadequate, supplement with a grow light for at least 6 hours per day. Monitor leaf color; pale or yellowing leaves may indicate too much direct sunlight, while elongated stems suggest insufficient light.

How do I care for Lemongrass?

Lemongrass thrives with bright, indirect sunlight, needing at least 6 hours daily. Water thoroughly when the top inch of soil feels dry, ensuring good drainage to prevent root rot. Maintain a consistently moist soil, but avoid overwatering. A well-draining potting mix is crucial for healthy growth. Fertilize every 2-4 weeks during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Maintain humidity levels around 50-60% by misting regularly or using a humidifier. Prune regularly to encourage bushier growth and remove any dead or yellowing leaves. Repot annually in spring to provide fresh soil and more room for growth. Protect from frost, as Lemongrass is sensitive to cold temperatures. Ensure good air circulation to prevent fungal diseases.

How do I propagate Lemongrass?

Lemongrass can be easily propagated through division, stem cuttings, or air layering. For division, carefully separate the plant clump into smaller sections, ensuring each section has healthy roots. Replant each section in a separate pot with well-draining soil. For stem cuttings, take a healthy stem cutting about 4-6 inches long. Remove the lower leaves and place the cutting in water. Once roots develop, transplant it into soil. Air layering involves making a small cut on a stem, wrapping it with moist sphagnum moss, and covering it with plastic wrap. Once roots emerge through the moss, cut the stem below the roots and plant it in soil. Keep the soil consistently moist and provide bright, indirect light for successful propagation.

Last updated: May 1, 2026 — Plant care data reviewed and verified by our editorial team.