Nasturtium Tropaeolum vs Rainbow Fern Plant Comparison

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

Nasturtium Tropaeolum

Nasturtium Tropaeolum

Tropaeolum majus

VS
Rainbow Fern

Rainbow Fern

Selaginella uncinata

Nasturtium Tropaeolum

Nasturtium Tropaeolum

Tropaeolum majus

Tropaeolum majus, commonly known as nasturtium, is an annual flowering plant known for its vibrant, edible flowers and peppery-flavored leaves. It is a sprawling plant that can grow as a ground cover or climb with support. The plant features round, shield-shaped leaves and spurred flowers in shades of orange, yellow, and red. While primarily grown outdoors in gardens and containers for its ornamental value and culinary uses, it can be challenging to maintain indoors due to its high light requirements and sprawling growth habit. People grow it for its bright colors, edible parts, and ability to attract pollinators.

Tropaeolaceae Andes Mountains of South America (Peru, Bolivia)
✨ Features: Edible flowers and leaves, attracts pollinators, natural pest repellent.
📖 Read Complete Nasturtium Tropaeolum Guide
Rainbow Fern

Rainbow Fern

Selaginella uncinata

Selaginella uncinata, commonly known as Rainbow Fern, is a creeping, mat-forming plant prized for its iridescent blue-green foliage. The shimmering effect is caused by the reflection of light off the leaf surfaces. It is not a true fern, but a spikemoss. While it can be grown indoors, it requires very high humidity and consistent moisture, making it a challenging houseplant. People grow it for its unique coloration and texture, adding a touch of the exotic to terrariums or humid environments.

Selaginellaceae China
✨ Features: Iridescent blue-green foliage, unique texture.
📖 Read Complete Rainbow Fern Guide

Quick Plant Comparison

Feature Nasturtium Tropaeolum Rainbow Fern
Light Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal flowering. Bright, indirect light. Avoid direct sunlight, which can scorch the delicate fronds.
Watering Every 2-3 days outdoors in warm weather, less frequently in cooler conditions. Indoor watering is difficult to predict, but likely every 5-7 days if attempted. Every 2-3 days, depending on humidity and temperature
Humidity 40-60% 70-90%
Temperature 15-24°C 18-24°C
Care Level Expert Expert
Growth Rate Fast Moderate
Max Height 0.3-1 meter (indoors, likely smaller and less vigorous) 15-30 cm
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining soil; a mix of potting soil, perlite, and compost is suitable. Avoid overly rich soil, as it can promote foliage growth at the expense of flowers. Well-draining, moisture-retentive mix such as peat moss, perlite, and vermiculite.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 10 minutes weekly outdoors, more if attempting indoor growth. 15-20 minutes weekly

🔬 Botanical Information — Comparing These Plants

Nasturtium Tropaeolum

Scientific Name Tropaeolum majus
Family Tropaeolaceae
Native To Andes Mountains of South America (Peru, Bolivia)
Also Known As Nasturtium, Garden Nasturtium, Indian Cress, Monk's Cress
Leaves The leaves of nasturtiums are round and shield-shaped, with a diameter of 5-10 cm. They are typically a vibrant green color and have a slightly waxy texture. The leaves are attached to the stem in the center, giving them a unique and distinctive appearance.
Flowers Nasturtiums readily flower outdoors in the right conditions. The flowers are spurred and come in shades of orange, yellow, and red. They have a delicate, peppery fragrance and are often used in salads and as garnishes. Flowering indoors is rare and requires intense supplemental lighting.

Rainbow Fern

Scientific Name Selaginella uncinata
Family Selaginellaceae
Native To China
Also Known As Rainbow Fern, Peacock Fern, Blue Fern, Spikemoss
Leaves Small, scale-like leaves arranged in overlapping rows along the stems. The leaves are typically a vibrant blue-green color with an iridescent sheen. They are delicate and finely textured.
Flowers Selaginella uncinata does not produce flowers in the typical sense. It reproduces via spores, which are produced in strobili (cone-like structures) at the tips of the stems. These are rarely seen indoors.

📏 Size & Growth — Plant Comparison

Nasturtium Tropaeolum

Height 0.3-1 meter (indoors, likely smaller and less vigorous)
Spread 0.3-1 meter (can spread wider outdoors)
Growth Rate Fast
Growth Pattern Nasturtiums have a sprawling growth habit, either trailing along the ground or climbing with support. They can reach up to 1 meter in height and spread, forming a dense mat of foliage and flowers.

Rainbow Fern

Height 15-30 cm
Spread 30-60 cm (can spread via creeping stems)
Growth Rate Moderate
Growth Pattern Creeping and mat-forming, spreading horizontally via rhizomes. It creates a dense, low-growing carpet of foliage.

🌱 Propagation — Comparing Plant Growth

Nasturtium Tropaeolum

Methods: Seed

Difficulty: Easy

Tips: Soak seeds in water for a few hours before planting. Sow directly into the soil or start indoors 4-6 weeks before the last frost. Keep soil moist until germination.

Rainbow Fern

Methods: Division, Stem cuttings

Difficulty: Moderate

Tips: Divide the plant at the roots or take stem cuttings and place them in a humid environment until they root. A propagation box or terrarium works well.

✨ Benefits & Features — Comparing Plant Value

Nasturtium Tropaeolum

Nasturtiums are unique for their edible flowers and leaves, which have a distinctive peppery flavor. They also act as a natural pest repellent, making them a valuable addition to vegetable gardens. Their vibrant colors and ease of growth make them a popular choice for gardeners.

  • ✓ Edible flowers and leaves provide a peppery flavor to dishes
  • ✓ Attracts pollinators to the garden, supporting local ecosystems
  • ✓ Acts as a natural pest repellent, reducing the need for chemical pesticides
  • ✓ Adds vibrant color and visual interest to outdoor spaces
  • ✓ Provides a fun and engaging gardening experience.
  • ⚠️ Toxic to pets

Rainbow Fern

The Rainbow Fern's iridescent blue-green foliage sets it apart from other ferns and houseplants. This shimmering effect is a result of structural coloration, where light interacts with the leaf's surface. It is not a true fern, but a spikemoss, belonging to the genus Selaginella.

  • ✓ Adds a unique visual element to indoor spaces
  • ✓ Creates a calming and relaxing atmosphere
  • ✓ Can be used in terrariums and vivariums
  • ✓ Non-toxic to pets
  • ✓ Offers a connection to nature indoors
  • 🐾 Pet Safe

📅 Maintenance Schedule — Plant Care Comparison

Nasturtium Tropaeolum

Repotting Not typically needed as they are annuals. If grown in containers, repotting may be necessary if the plant becomes root-bound, though this is unlikely to occur indoors.
Pruning Pinch back stems to encourage bushier growth and more flowers. Remove spent flowers to prolong blooming.
Fertilizing Low-nitrogen fertilizer, applied sparingly every 4-6 weeks during the growing season. High nitrogen fertilizers will promote leaf growth over flower production.
Seasonal Care In spring and summer, provide regular watering and fertilization. In fall, reduce watering and allow the plant to set seed. Nasturtiums are annuals and will die back in winter.

Rainbow Fern

Repotting Every 1-2 years, or when the plant becomes root-bound. Choose a slightly larger pot.
Pruning Trim any dead or damaged fronds to maintain appearance and prevent disease.
Fertilizing Diluted liquid fertilizer (half strength) every 2-4 weeks during the growing season (spring and summer).
Seasonal Care Reduce watering slightly in winter when growth slows. Maintain humidity levels year-round. Provide supplemental light if needed during shorter days.

🌞 Light Requirements

Nasturtium Tropaeolum

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

Low light tolerant: ❌ No

Rainbow Fern

Bright, indirect light. Avoid direct sunlight, which can scorch the delicate fronds.

Low light tolerant: ❌ No

💧 Watering Needs

Nasturtium Tropaeolum

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Yellowing leaves indicate overwatering; wilting leaves indicate underwatering.

Rainbow Fern

Keep the soil consistently moist but not soggy. Water when the top of the soil feels slightly dry to the touch. Overwatering can lead to root rot, while underwatering will cause the fronds to dry out and turn brown. Use distilled or rainwater to avoid mineral buildup.

🌡️ Temperature & Humidity

Nasturtium Tropaeolum

Temperature: 15-24°C

Humidity: 40-60%

Rainbow Fern

Temperature: 18-24°C

Humidity: 70-90%

🤔 Which Plant Is Right For You?

Nasturtium Tropaeolum

Nasturtium Tropaeolum

Tropaeolum majus
Care: Expert Time: 10 minutes weekly outdoors, more if attempting indoor growth. Beginner: No

Gardeners looking for an edible and ornamental plant to add color and interest to their outdoor spaces.

✅ Choose This Plant If...

  • You want edible flowers and leaves for salads and garnishes
  • You need a plant to attract pollinators to your garden
  • You want a natural pest repellent for your vegetable garden
  • You enjoy vibrant colors in your outdoor space
  • You are an experienced gardener willing to experiment with growing a sun-loving plant indoors.

❌ Skip This Plant If...

  • You have pets that might ingest the plant
  • You lack a sunny location to provide adequate light
  • You prefer low-maintenance indoor plants.
📍 Ideal Location: Outdoors in a sunny garden bed or container. A very sunny windowsill is the only possible indoor location, but success is unlikely.
🎨 Style: Cottagecore, Bohemian, Eclectic
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, nasturtiums contain mustard oil glycosides, which can cause mild gastrointestinal upset in dogs, cats, and horses. Symptoms include vomiting, diarrhea, and drooling. All parts of the plant are potentially toxic.
Rainbow Fern

Rainbow Fern

Selaginella uncinata
Care: Expert Time: 15-20 minutes weekly Beginner: No

Experienced plant enthusiasts who can provide a humid environment like a terrarium.

✅ Choose This Plant If...

  • You want a unique and visually striking plant with iridescent foliage.
  • You can provide a consistently humid environment, such as a terrarium.
  • You enjoy the challenge of caring for demanding plants.
  • You want to add a touch of the exotic to your indoor garden.
  • You appreciate the delicate beauty of ferns and mosses.

❌ Skip This Plant If...

  • You struggle to maintain consistent watering schedules.
  • You live in a dry climate and cannot provide high humidity.
  • You are a beginner plant owner looking for low-maintenance options.
📍 Ideal Location: Bathroom with bright, indirect light or a terrarium.
🎨 Style: Tropical, Bohemian, Eclectic
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Selaginella species are generally considered non-toxic to dogs, cats, and horses.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Rainbow Fern ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

📈

Nasturtium Tropaeolum has fast growth, while Rainbow Fern grows moderate.

💡 Pro Tips For Comparing These Plants

Nasturtium Tropaeolum Care Tips

Nasturtiums are easy to grow outdoors in sunny locations with well-draining soil. Indoor cultivation is challenging due to high light requirements and the plant's sprawling growth habit. Providing adequate light and avoiding overwatering are crucial for indoor success, which is rarely achieved.

  • Provide at least 6 hours of direct sunlight daily for optimal flowering
  • Avoid overwatering to prevent root rot
  • Use a low-nitrogen fertilizer to encourage flower production
  • Pinch back stems to promote bushier growth
  • Collect seeds at the end of the season to replant next year.
❄️ Winter: Nasturtiums are annuals and do not survive winter. Collect seeds in the fall to replant in the spring.
☀️ Summer: Provide regular watering and fertilization during the summer growing season. Protect from intense afternoon sun in very hot climates to prevent leaf scorch.

Rainbow Fern Care Tips

Rainbow Ferns are challenging houseplants due to their high humidity and moisture requirements. They thrive in terrariums or enclosed environments where humidity can be maintained. Consistent watering and bright, indirect light are crucial for their survival indoors. It is primarily an outdoor plant in tropical climates.

  • Use distilled or rainwater to avoid mineral buildup on the fronds.
  • Maintain high humidity by misting regularly or using a humidifier.
  • Provide bright, indirect light to enhance the iridescent coloration.
  • Ensure good drainage to prevent root rot.
  • Monitor for pests and treat promptly.
❄️ Winter: Reduce watering slightly, but maintain high humidity. Ensure the plant receives adequate light, supplementing with artificial light if necessary. Avoid placing near drafts or heating vents.
☀️ Summer: Water more frequently to keep the soil consistently moist. Protect from direct sunlight to prevent scorching. Increase ventilation to prevent fungal diseases.

⚠️ Common Problems & Solutions — Plant Care Comparison

Nasturtium Tropaeolum

Common Issues: Aphids, whiteflies, root rot, lack of flowering
Solutions: Treat aphids and whiteflies with insecticidal soap or neem oil. Prevent root rot by ensuring well-draining soil and avoiding overwatering. Encourage flowering by providing full sun and using a low-nitrogen fertilizer.

Rainbow Fern

Common Issues: Browning fronds, Root rot, Lack of iridescence, Pest infestations (spider mites)
Solutions: Increase humidity, improve drainage, provide brighter indirect light, treat with insecticidal soap or neem oil.

❓ Frequently Asked Questions — Comparing These Plants

Nasturtium Tropaeolum

What are the light requirements for Nasturtium Tropaeolum?

Nasturtium Tropaeolum thrives in full sun, which translates to at least 6 hours of direct sunlight per day. In hotter climates, provide some afternoon shade to prevent scorching of the leaves and flowers. Insufficient light can lead to leggy growth and reduced blooming.

How do I care for Nasturtium Tropaeolum?

Nasturtium Tropaeolum thrives in well-draining soil and prefers full sun to partial shade. Water regularly, allowing the soil to dry slightly between waterings. Avoid overwatering, which can lead to root rot. Fertilize sparingly, as excessive fertilization can promote leaf growth at the expense of flowers.

How do I propagate Nasturtium Tropaeolum?

Nasturtium Tropaeolum is most commonly propagated by seed. Sow seeds directly into the garden in spring after the last frost or start them indoors 4-6 weeks prior. Soak the seeds in water overnight before planting to improve germination.

Rainbow Fern

What are the light requirements for Rainbow Fern?

Rainbow Fern requires bright, indirect light to maintain its vibrant coloration. Direct sunlight can scorch its delicate fronds, so avoid placing it in direct sun exposure. An east-facing window is often ideal, providing gentle morning light. A north-facing window can also work, but supplemental lighting might be necessary if the plant doesn’t receive enough natural light. If placed near a south or west-facing window, use a sheer curtain to filter the light. Insufficient light can cause the colors to fade and the plant to become leggy. Observe the plant’s response to light and adjust its placement accordingly.

How do I care for Rainbow Fern?

Rainbow Fern thrives in bright, indirect light and consistently moist soil. Water thoroughly when the top inch of soil feels slightly dry, using distilled or filtered water to avoid mineral buildup. Maintain high humidity levels, ideally above 70%, through regular misting, a humidifier, or a pebble tray. Plant in a well-draining, acidic potting mix. Fertilize lightly during the growing season (spring and summer) with a diluted liquid fertilizer. Avoid direct sunlight, which can scorch the delicate foliage. Maintain temperatures between 60-75°F (15-24°C). Prune any dead or damaged fronds to encourage new growth. Ensure good air circulation to prevent fungal diseases. Repot only when necessary, usually every 1-2 years, using a slightly larger pot.

How do I propagate Rainbow Fern?

Rainbow Fern can be propagated by division or spores.

Last updated: May 5, 2026 — Plant care data reviewed and verified by our editorial team.