Flowering Kale vs Rainbow Fern Plant Comparison

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

Flowering Kale

Flowering Kale

Brassica oleracea var. acephala

VS
Rainbow Fern

Rainbow Fern

Selaginella uncinata

Flowering Kale

Flowering Kale

Brassica oleracea var. acephala

Flowering kale is a cool-season biennial grown as an annual for its vibrant, colorful foliage. It is not grown for edible leaves like its close relative, edible kale. The plant forms a rosette of ruffled or frilly leaves in shades of white, pink, purple, or red, surrounded by outer green leaves. It is primarily an outdoor plant, thriving in cooler temperatures and full sun. People grow it for its ornamental value, adding color and texture to gardens and containers during the fall and winter months.

Brassicaceae Europe
✨ Features: Provides vibrant color in cool-season gardens.
📖 Read Complete Flowering Kale 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 Flowering Kale Rainbow Fern
Light Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal color development. Bright, indirect light. Avoid direct sunlight, which can scorch the delicate fronds.
Watering Every 3-7 days, depending on weather and soil drainage. Every 2-3 days, depending on humidity and temperature
Humidity 40-60% 70-90%
Temperature 4-18°C 18-24°C
Care Level Expert Expert
Growth Rate Moderate Moderate
Max Height 20-40 cm 15-30 cm
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining potting mix or garden soil enriched with organic matter. Well-draining, moisture-retentive mix such as peat moss, perlite, and vermiculite.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 5 minutes weekly 15-20 minutes weekly

🔬 Botanical Information — Comparing These Plants

Flowering Kale

Scientific Name Brassica oleracea var. acephala
Family Brassicaceae
Native To Europe
Also Known As Flowering Kale, Ornamental Kale, Ornamental Cabbage
Leaves The leaves of flowering kale are broad and ruffled or frilly, depending on the variety. They can range in size from 15-30 cm in diameter. The outer leaves are typically green, while the inner leaves display vibrant colors such as white, pink, purple, or red. The texture is often slightly waxy.
Flowers Flowering kale may produce small yellow flowers if it overwinters and bolts in the spring. However, it is primarily grown for its foliage, and the flowers are not particularly showy. Flowering is often considered undesirable as it signals the end of the plant's ornamental display.

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

Flowering Kale

Height 20-40 cm
Spread 20-40 cm
Growth Rate Moderate
Growth Pattern Flowering kale grows in a rosette shape, with tightly packed leaves forming a dense head. The outer leaves are typically green, while the inner leaves display vibrant colors like white, pink, purple, or red. It does not spread aggressively.

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

Flowering Kale

Methods: Seed

Difficulty: Easy

Tips: Sow seeds indoors 6-8 weeks before the last expected frost or directly outdoors in late summer for fall/winter color. Provide consistent moisture and light for 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

Flowering Kale

Flowering kale is unique for its vibrant colors that intensify in cool weather, providing ornamental value during the fall and winter months when many other plants are dormant. Unlike edible kale, it is primarily grown for its visual appeal rather than its flavor.

  • ✓ Adds vibrant color to cool-season gardens
  • ✓ Provides visual interest during the dormant season
  • ✓ Attracts beneficial insects
  • ✓ Easy to grow outdoors in suitable climates
  • ✓ Offers a unique textural element to garden designs
  • ⚠️ 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

Flowering Kale

Repotting Not typically repotted as it is grown as an annual.
Pruning Remove yellowing or damaged leaves to maintain appearance.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-4 weeks during the growing season.
Seasonal Care In fall and winter, provide protection from frost if temperatures drop below freezing. In spring, plants may bolt as temperatures rise. Remove spent flower stalks to encourage continued foliage production.

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

Flowering Kale

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

Low light tolerant: ❌ No

Rainbow Fern

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

Low light tolerant: ❌ No

💧 Watering Needs

Flowering Kale

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Ensure good drainage. Signs of overwatering include yellowing leaves and a soggy soil. Underwatering is indicated by wilting leaves.

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

Flowering Kale

Temperature: 4-18°C

Humidity: 40-60%

Rainbow Fern

Temperature: 18-24°C

Humidity: 70-90%

🤔 Which Plant Is Right For You?

Flowering Kale

Flowering Kale

Brassica oleracea var. acephala
Care: Expert Time: 5 minutes weekly Beginner: No

Gardeners looking to add vibrant color to their fall and winter gardens.

✅ Choose This Plant If...

  • You want vibrant fall and winter color in your garden.
  • You have a sunny outdoor space with cool temperatures.
  • You enjoy container gardening with seasonal plants.
  • You want a low-maintenance plant for outdoor displays.
  • You appreciate the unique texture and form of ornamental foliage.

❌ Skip This Plant If...

  • You have limited sunlight indoors.
  • You live in a consistently warm climate.
  • You have pets that might ingest the plant.
  • You are looking for a long-term indoor houseplant.
📍 Ideal Location: Outdoor gardens, patios, balconies, or decks with full sun exposure.
🎨 Style: Cottage, Rustic, Fall, Winter
🏠 Apartment Friendly: Limited
⚠️ All parts of the plant are considered mildly toxic to dogs, cats, and horses. Symptoms include gastrointestinal upset, such as vomiting and diarrhea. The ASPCA lists Brassica oleracea as containing glucosinolates, which can cause irritation.
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

🌿

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

Flowering Kale Care Tips

Flowering kale is primarily an outdoor plant and requires full sun and cool temperatures to thrive. It is challenging to maintain indoors due to its high light requirements and sensitivity to warm, dry air. Indoor plants often become leggy and lose their color.

  • Plant in well-draining soil to prevent root rot.
  • Provide at least 6 hours of direct sunlight daily for best color.
  • Water regularly, but avoid overwatering.
  • Fertilize every 2-4 weeks with a balanced liquid fertilizer.
  • Protect from extreme cold or frost if necessary.
❄️ Winter: Protect from extreme cold or frost by covering with a blanket or moving to a sheltered location. Reduce watering frequency during colder periods. Ensure adequate sunlight exposure.
☀️ Summer: Flowering kale typically does not thrive in hot summer temperatures. Provide shade during the hottest part of the day to prevent bolting. Ensure adequate watering to prevent stress.

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

Flowering Kale

Common Issues: Aphids, Cabbage worms, Root rot, Bolting (premature flowering)
Solutions: Aphids: Insecticidal soap or neem oil. Cabbage worms: Handpick or use Bacillus thuringiensis (Bt). Root rot: Improve drainage and reduce watering. Bolting: Keep plants cool and well-watered.

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

Flowering Kale

What are the light requirements for Flowering Kale?

Flowering Kale needs at least six hours of direct sunlight per day to develop its best color. Insufficient light can lead to leggy growth and dull coloration. When planting, choose a location that receives full sun exposure. If growing in containers, rotate the plants regularly to ensure even light exposure on all sides.

How do I care for Flowering Kale?

Flowering Kale thrives in cool temperatures (40-70°F) and requires at least 6 hours of sunlight daily. Plant in well-draining soil, enriched with compost or other organic matter. Water regularly, keeping the soil consistently moist but not waterlogged. Fertilize every 2-3 weeks with a balanced fertilizer during the growing season to promote vibrant color.

How do I propagate Flowering Kale?

Flowering Kale is primarily grown from seed, but propagation through stem cuttings is possible, though less common. Take stem cuttings from healthy, non-flowering shoots in late summer or early fall. Dip the cut end in rooting hormone and plant in a well-draining potting mix. Keep the cuttings moist and in a warm, humid environment until roots develop.

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 3, 2026 — Plant care data reviewed and verified by our editorial team.