Japanese Aralia vs Pondweed Plant Comparison

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

Japanese Aralia

Japanese Aralia

Fatsia japonica

VS
Pondweed

Pondweed

Potamogeton natans

Japanese Aralia

Japanese Aralia

Fatsia japonica

Fatsia japonica, or Japanese Aralia, is an evergreen shrub or small tree known for its large, palmate (hand-shaped) leaves. It typically grows to 1-3 meters tall indoors, though can reach greater heights outdoors. The leaves are glossy, deeply lobed, and can be up to 30-50 cm across. While it can be grown indoors, it thrives outdoors in temperate climates. People grow it for its bold foliage and architectural presence, adding a tropical or exotic touch to gardens and interiors. Indoor cultivation can be challenging due to its need for bright light and cool temperatures.

Araliaceae Japan
✨ Features: Bold foliage, architectural presence.
📖 Read Complete Japanese Aralia Guide
Pondweed

Pondweed

Potamogeton natans

Potamogeton natans, commonly known as broad-leaved pondweed, is an aquatic perennial herb found in still or slow-flowing freshwater habitats. It features submerged and floating leaves. The floating leaves are oval to elliptical, leathery, and have long petioles. Submerged leaves are usually absent or reduced to bladeless petioles. It spreads via rhizomes, forming dense mats. While it plays an important ecological role in its natural habitat, it is rarely cultivated intentionally due to its aggressive growth and specific environmental needs. It is primarily an outdoor plant.

Potamogetonaceae Eurasia, North America
✨ Features: Provides habitat and food for aquatic wildlife, oxygenates water, helps control algae growth.
📖 Read Complete Pondweed Guide

Quick Plant Comparison

Feature Japanese Aralia Pondweed
Light Bright indirect light to partial shade. Avoid direct sunlight, especially during the hottest part of the day. Full sun to partial shade
Watering Every 7-10 days, adjust based on environmental conditions and pot size. Constantly submerged
Humidity 40-60% 100%
Temperature 16-21°C 10-25°C
Care Level Expert Expert
Growth Rate Moderate Fast
Max Height 1-3 meters (indoors), up to 5 meters (outdoors) Variable, depending on water depth, typically up to 1 meter.
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining potting mix, such as a blend of peat moss, perlite, and vermiculite. Pond sediment or aquatic planting media
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 30 minutes weekly during growing season for pruning and algae control.

🔬 Botanical Information — Comparing These Plants

Japanese Aralia

Scientific Name Fatsia japonica
Family Araliaceae
Native To Japan
Also Known As Japanese Aralia, Fig-leaf Palm, False Castor Oil Plant
Leaves Large, palmate leaves with 7-9 deep lobes. The leaves are glossy, dark green, and can reach up to 50 cm in diameter. The texture is smooth and slightly leathery.
Flowers Rarely flowers indoors. Outdoors, it produces clusters of small, white flowers in late autumn or early winter, followed by black berries.

Pondweed

Scientific Name Potamogeton natans
Family Potamogetonaceae
Native To Eurasia, North America
Also Known As Broad-leaved Pondweed, Floating Pondweed
Leaves Floating leaves are oval to elliptical, leathery, and typically 5-10 cm long. They are dark green and have long petioles. Submerged leaves are usually absent or reduced to bladeless petioles.
Flowers It produces small, inconspicuous flowers on a spike that emerges above the water surface. Flowering typically occurs in summer. Flowers are not showy and are primarily wind-pollinated. Rarely seen indoors.

📏 Size & Growth — Plant Comparison

Japanese Aralia

Height 1-3 meters (indoors), up to 5 meters (outdoors)
Spread 1-2 meters
Growth Rate Moderate
Growth Pattern Upright, bushy shrub. It can become leggy if not provided with enough light. The plant develops a sturdy stem as it matures.

Pondweed

Height Variable, depending on water depth, typically up to 1 meter.
Spread Spreads aggressively via rhizomes, can cover large areas.
Growth Rate Fast
Growth Pattern Spreads horizontally via rhizomes, forming dense mats on the water surface. Submerged stems grow upwards from the rhizomes, supporting the floating leaves.

🌱 Propagation — Comparing Plant Growth

Japanese Aralia

Methods: Stem cuttings, Seed

Difficulty: Moderate

Tips: Take stem cuttings in spring or summer. Dip the cut end in rooting hormone and plant in moist potting mix. Keep the cutting in a warm, humid environment until roots develop.

Pondweed

Methods: Rhizome division, seed

Difficulty: Easy

Tips: Divide rhizomes in spring or early summer. Plant rhizome sections in pond sediment or aquatic planting media. Seeds can be collected and sown in spring.

✨ Benefits & Features — Comparing Plant Value

Japanese Aralia

The large, palmate leaves give it a unique and tropical appearance. It's relatively tolerant of neglect once established, but requires specific conditions to thrive indoors. Its bold foliage makes it a striking addition to any space.

  • ✓ Adds a bold, tropical aesthetic to indoor spaces.
  • ✓ Provides a sense of connection to nature.
  • ✓ Can improve indoor air quality by absorbing some pollutants.
  • ✓ Offers a visually interesting focal point.
  • ✓ Can create a calming and relaxing atmosphere.
  • ⚠️ Toxic to pets

Pondweed

Broad-leaved pondweed is characterized by its distinct floating leaves and its ability to form dense mats in aquatic environments. It plays a vital role in supporting aquatic ecosystems.

  • ✓ Provides habitat for aquatic wildlife
  • ✓ Oxygenates pond water
  • ✓ Helps control algae growth
  • ✓ Adds a natural aesthetic to ponds
  • ✓ Supports biodiversity in aquatic ecosystems
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Japanese Aralia

Repotting Every 2-3 years, or when the plant becomes root-bound.
Pruning Prune to maintain shape and remove any dead or damaged leaves. Pruning is best done in spring.
Fertilizing Balanced liquid fertilizer (20-20-20) diluted to half strength, every 4-6 weeks during the growing season (spring and summer).
Seasonal Care In winter, reduce watering and avoid fertilizing. Ensure the plant receives adequate light. In summer, provide ample moisture and protect from direct sunlight.

Pondweed

Repotting Not applicable as it is grown in ponds. If in a container, division and replanting may be needed annually due to aggressive growth.
Pruning Regularly prune to control spread and remove dead or decaying foliage.
Fertilizing Not typically needed in natural ponds. If grown in a controlled environment, use aquatic plant fertilizer sparingly during the growing season.
Seasonal Care In winter, the plant may die back, with rhizomes surviving underwater. Remove dead foliage in spring. In summer, growth is rapid, and regular thinning may be necessary.

🌞 Light Requirements

Japanese Aralia

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

Low light tolerant: ❌ No

Pondweed

Full sun to partial shade

Low light tolerant: ❌ No

💧 Watering Needs

Japanese Aralia

Water thoroughly when the top inch of soil feels dry to the touch. Ensure good drainage. Overwatering can lead to root rot, indicated by yellowing leaves and a musty smell. Underwatering results in drooping leaves and dry, crispy edges.

Pondweed

Requires submersion in water. Water level should be maintained consistently. Signs of underwatering are wilting or drying of leaves above the water surface. Overwatering is not applicable as it is a submerged plant.

🌡️ Temperature & Humidity

Japanese Aralia

Temperature: 16-21°C

Humidity: 40-60%

Pondweed

Temperature: 10-25°C

Humidity: 100%

🤔 Which Plant Is Right For You?

Japanese Aralia

Japanese Aralia

Fatsia japonica
Care: Expert Time: 15 minutes weekly Beginner: No

Experienced plant enthusiasts who can provide the specific conditions required for this plant to thrive indoors.

✅ Choose This Plant If...

  • You want a bold, architectural plant with large, distinctive leaves.
  • You have a bright, cool location indoors.
  • You are an experienced plant owner familiar with pest control.
  • You want to add a tropical touch to your indoor space.
  • You are prepared to monitor humidity and watering carefully.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You have limited natural light indoors.
  • You are a beginner plant owner.
📍 Ideal Location: Bright, cool room with indirect light, such as a sunroom or near a north-facing window.
🎨 Style: Tropical, Bohemian, Modern
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Fatsia japonica is toxic to dogs, cats, and horses. Symptoms include vomiting, diarrhea, and abdominal pain. All parts of the plant are considered toxic.
Pondweed

Pondweed

Potamogeton natans
Care: Expert Time: 30 minutes weekly during growing season for pruning and algae control. Beginner: No

Pond owners seeking a naturalistic aquatic plant for wildlife habitat and oxygenation.

✅ Choose This Plant If...

  • You have a pond or water garden and want to provide habitat for wildlife.
  • You want a natural way to oxygenate your pond water.
  • You are looking for a plant that can help control algae growth.
  • You understand the aggressive growth habits of this plant and are prepared to manage it.
  • You are interested in native aquatic plants and their ecological roles.

❌ Skip This Plant If...

  • You do not have a pond or water garden.
  • You are looking for an indoor plant.
  • You are not prepared to manage the aggressive spread of this plant.
  • You have pets that may ingest the plant.
  • You are looking for a low-maintenance plant.
📍 Ideal Location: Outdoor pond or water garden
🎨 Style: Naturalistic, Wild, Pond
🏠 Apartment Friendly: No
⚠️ Potamogeton species can be toxic to dogs, cats, and horses. Symptoms include gastrointestinal upset. The toxic principle is unknown, but some species can accumulate nitrates. All parts of the plant are potentially toxic.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Neither - caution
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

📈

Japanese Aralia has moderate growth, while Pondweed grows fast.

💡 Pro Tips For Comparing These Plants

Japanese Aralia Care Tips

Fatsia japonica is primarily an outdoor plant and can be challenging to grow indoors. It requires bright indirect light, consistent moisture, and cool temperatures. Maintaining adequate humidity and preventing pests are crucial for indoor success. It is also toxic to pets.

  • Provide bright, indirect light to prevent leggy growth.
  • Maintain consistent moisture, but avoid overwatering.
  • Wipe leaves regularly to remove dust and prevent pests.
  • Ensure good air circulation to prevent fungal diseases.
  • Monitor for pests and treat promptly.
❄️ Winter: Reduce watering frequency. Ensure adequate light. Maintain cool temperatures. Avoid fertilizing.
☀️ Summer: Provide ample moisture. Protect from direct sunlight. Increase humidity if possible. Fertilize regularly.

Pondweed Care Tips

Broad-leaved pondweed is an outdoor aquatic plant that is challenging to grow indoors. It requires full sun, constant submersion, and can quickly outgrow any container. It is best suited for ponds or water gardens. Indoor cultivation is not recommended.

  • Regularly prune to control spread.
  • Monitor water quality and adjust nutrient levels as needed.
  • Remove dead or decaying foliage to prevent nutrient buildup.
  • Provide adequate sunlight for optimal growth.
  • Consider introducing beneficial bacteria to help control algae.
❄️ Winter: The plant may die back in winter, with rhizomes surviving underwater. Remove dead foliage to prevent decomposition and nutrient buildup. Ensure the pond does not completely freeze over to allow for gas exchange.
☀️ Summer: Growth is rapid in summer. Regular thinning may be necessary to prevent excessive spread. Ensure adequate sunlight and water quality. Monitor for algae growth and take corrective measures as needed.

⚠️ Common Problems & Solutions — Plant Care Comparison

Japanese Aralia

Common Issues: Spider mites, Aphids, Root rot, Leaf spot
Solutions: Spider mites: Increase humidity and treat with insecticidal soap. Aphids: Wash off with water or treat with insecticidal soap. Root rot: Improve drainage and reduce watering frequency. Leaf spot: Remove affected leaves and improve air circulation.

Pondweed

Common Issues: Algae growth, excessive spread, nutrient imbalances, herbivore damage (e.g., snails, fish)
Solutions: Control algae with algaecides or by improving water circulation. Manage spread by physically removing excess growth. Test water and adjust nutrient levels as needed. Introduce or remove herbivores as appropriate.

❓ Frequently Asked Questions — Comparing These Plants

Japanese Aralia

What are the light requirements for Japanese Aralia?

Japanese Aralia thrives in bright, indirect light. Direct sunlight can burn its delicate leaves, so avoid placing it in a south-facing window without any protection. An east or west-facing window is ideal, where it will receive gentle morning or afternoon light. If your space lacks sufficient natural light, consider supplementing with a grow light. Rotate the plant regularly to ensure even growth on all sides. Insufficient light can lead to leggy growth and pale leaves.

How do I care for Japanese Aralia?

To care for your Japanese Aralia, provide bright, indirect light. Avoid direct sunlight, which can scorch the leaves. Water thoroughly when the top inch of soil feels dry to the touch, ensuring proper drainage. Reduce watering in winter. Maintain moderate humidity levels. Fertilize every 2-3 weeks 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 to maintain shape and remove any dead or damaged leaves. Keep temperatures between 60-75°F (15-24°C). Regularly check for pests and address any infestations promptly.

How do I propagate Japanese Aralia?

Japanese Aralia can be propagated through stem cuttings or air layering. For stem cuttings, take a 4-6 inch cutting from a healthy stem. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cutting in a well-draining potting mix and keep it moist. Cover with a plastic bag to increase humidity. For air layering, make a small cut on a stem and wrap it with moist sphagnum moss. Cover the moss with plastic wrap and secure it with tape. Once roots develop, cut the stem below the roots and plant it in a pot. Both methods are best done in spring or early summer.

Pondweed

What are the light requirements for Pondweed?

Pondweed thrives in moderate to high light conditions. Submerged varieties generally require more intense light than floating types. Aim for at least 6-8 hours of light per day. Insufficient light can lead to leggy growth, yellowing leaves, and reduced oxygen production. If using artificial lighting, opt for full-spectrum LED or fluorescent lights designed for aquatic plants. Position the light source close to the water surface for maximum penetration. Observe your Pondweed closely; if the leaves appear pale or stretched, increase the light intensity or duration. Conversely, if algae growth becomes excessive, reduce the light levels slightly. Natural sunlight is beneficial, but avoid direct sunlight for prolonged periods, as it can overheat the water and promote algae blooms.

How do I care for Pondweed?

Caring for Pondweed involves maintaining suitable water conditions, providing adequate light, and ensuring proper nutrient levels. Submerged Pondweed requires a stable water temperature between 60-75°F (15-24°C). Water quality is paramount; regular water changes (25-50% weekly) are essential to remove excess nutrients and prevent algae blooms. Provide moderate to high light levels, ideally 6-8 hours per day. Nutrient supplementation may be necessary, especially in closed systems like aquariums. Use liquid fertilizers formulated for aquatic plants, following the manufacturer’s instructions carefully to avoid over-fertilization. Prune regularly to maintain the desired shape and size, removing any dead or decaying leaves. Ensure proper water circulation to prevent stagnant areas and promote healthy growth. Monitor for pests and address any infestations promptly.

How do I propagate Pondweed?

Pondweed can be easily propagated through division or stem cuttings.

Last updated: April 24, 2026 — Plant care data reviewed and verified by our editorial team.