Boston Fern vs Flowering Kale Plant Comparison

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

Boston Fern

Boston Fern

Nephrolepis exaltata

VS
Flowering Kale

Flowering Kale

Brassica oleracea var. acephala

Boston Fern

Boston Fern

Nephrolepis exaltata

The Boston Fern is a classic houseplant known for its graceful, arching fronds. It's a terrestrial fern, naturally found in humid forests and swamps. Its lush green foliage creates a soft, textured appearance, making it a popular choice for adding a touch of nature to indoor spaces. People grow it for its aesthetic appeal, air-purifying qualities (though not definitively proven by NASA), and relatively easy care, provided its humidity needs are met. It is primarily an outdoor plant but can adapt to indoor conditions with proper care.

Nephrolepidaceae Tropical regions worldwide, particularly the Americas
✨ Features: Air purifying (though not definitively proven by NASA), adds a lush, tropical feel to indoor spaces
📖 Read Complete Boston Fern Guide
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

Quick Plant Comparison

Feature Boston Fern Flowering Kale
Light Bright, indirect light. Avoid direct sunlight, which can scorch the fronds. Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal color development.
Watering Every 2-5 days, depending on humidity and light levels Every 3-7 days, depending on weather and soil drainage.
Humidity 60-80% 40-60%
Temperature 18-24°C 4-18°C
Care Level Moderate Expert
Growth Rate Moderate Moderate
Max Height 0.3-1 meter (indoors) 20-40 cm
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil Well-draining potting mix rich in organic matter, such as peat moss or coco coir Well-draining potting mix or garden soil enriched with organic matter.
Beginner Friendly With Caution ❌ No
Weekly Maintenance 10-15 minutes weekly 5 minutes weekly

🔬 Botanical Information — Comparing These Plants

Boston Fern

Scientific Name Nephrolepis exaltata
Family Nephrolepidaceae
Native To Tropical regions worldwide, particularly the Americas
Also Known As Boston Fern, Sword Fern
Leaves The leaves, or fronds, are pinnately compound, meaning they are composed of many small leaflets (pinnae) arranged along a central stem. The pinnae are typically bright green, lance-shaped, and have slightly serrated edges. The texture is delicate and feathery.
Flowers Boston Ferns do not flower indoors. They reproduce via spores, which are located on the underside of the fronds.

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.

📏 Size & Growth — Plant Comparison

Boston Fern

Height 0.3-1 meter (indoors)
Spread 0.3-1 meter
Growth Rate Moderate
Growth Pattern The Boston Fern grows in a clumping, arching habit. New fronds emerge from the center of the plant, gradually unfurling and cascading outwards.

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.

🌱 Propagation — Comparing Plant Growth

Boston Fern

Methods: Division, Spores

Difficulty: Moderate

Tips: Divide the plant at the root ball, ensuring each division has healthy fronds and roots. Propagating from spores is more challenging and requires a sterile environment.

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.

✨ Benefits & Features — Comparing Plant Value

Boston Fern

Boston Ferns are known for their long, arching fronds that create a cascading effect. They require higher humidity than many other common houseplants, making them a bit more challenging to care for indoors.

  • ✓ Adds a touch of nature and elegance to indoor spaces.
  • ✓ Creates a relaxing and calming atmosphere.
  • ✓ Can help to improve indoor air quality (though not definitively proven).
  • ✓ Provides a sense of accomplishment when successfully cared for.
  • ✓ Offers a visually appealing texture and color contrast to other houseplants.
  • 🌬️ NASA-verified air purifier
  • 🐾 Pet Safe

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

📅 Maintenance Schedule — Plant Care Comparison

Boston Fern

Repotting Every 1-2 years, or when the plant becomes root-bound
Pruning Remove dead or yellowing fronds to maintain appearance and encourage new growth.
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 frequency as growth slows. Maintain humidity levels. In summer, increase watering and consider moving the plant to a more humid location.

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.

🌞 Light Requirements

Boston Fern

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

Low light tolerant: ❌ No

Flowering Kale

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

Low light tolerant: ❌ No

💧 Watering Needs

Boston Fern

Keep the soil consistently moist but not soggy. Water when the top inch of soil feels dry to the touch. Overwatering can lead to root rot, indicated by yellowing or browning fronds. Underwatering results in crispy, dry fronds.

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.

🌡️ Temperature & Humidity

Boston Fern

Temperature: 18-24°C

Humidity: 60-80%

Flowering Kale

Temperature: 4-18°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Boston Fern

Boston Fern

Nephrolepis exaltata
Care: Moderate Time: 10-15 minutes weekly Beginner: With-caution

Individuals who can provide consistent moisture and high humidity, such as those with humidifiers or bathrooms with natural light.

✅ Choose This Plant If...

  • You want a classic, elegant houseplant that adds a touch of greenery to your home.
  • You are looking for a plant that is non-toxic to pets.
  • You can provide the high humidity levels this plant needs to thrive.
  • You have a bright, indirectly lit space where the fern can flourish.
  • You enjoy the challenge of providing specific care requirements to keep a plant healthy.

❌ Skip This Plant If...

  • You struggle to maintain consistent watering schedules.
  • You live in a very dry climate and cannot provide adequate humidity.
  • You don't have a location with bright, indirect light.
📍 Ideal Location: Bathroom with natural light, bright kitchen, or any room with high humidity
🎨 Style: Traditional, Bohemian, Tropical
🏠 Apartment Friendly: Limited
🌬️ Air Purifying: Yes (NASA verified)
⚠️ According to the ASPCA, Boston Ferns are non-toxic to dogs, cats, and horses.
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.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

🎯

Boston Fern is rated Moderate care level, while Flowering Kale is Expert.

💡 Pro Tips For Comparing These Plants

Boston Fern Care Tips

Boston Ferns require consistent moisture and high humidity to thrive indoors. Maintaining adequate humidity is the biggest challenge. They are not drought-tolerant and will suffer in dry environments. Provide bright, indirect light and regular fertilization during the growing season.

  • Mist the fronds regularly to increase humidity.
  • Place the pot on a pebble tray filled with water.
  • Use a humidifier to maintain consistent humidity levels.
  • Water thoroughly, allowing excess water to drain away.
  • Avoid placing the plant near drafts or heat sources.
❄️ Winter: Reduce watering frequency in winter as growth slows. Maintain humidity levels by misting or using a humidifier. Avoid placing the plant near cold drafts.
☀️ Summer: Increase watering frequency in summer as the plant actively grows. Provide shade from direct sunlight to prevent scorching. Consider moving the plant to a more humid location, such as a bathroom or shaded patio.

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.

⚠️ Common Problems & Solutions — Plant Care Comparison

Boston Fern

Common Issues: Browning fronds, Yellowing fronds, Pest infestations (spider mites, mealybugs), Root rot
Solutions: Browning fronds: Increase humidity. | Yellowing fronds: Adjust watering (avoid overwatering). | Pest infestations: Treat with insecticidal soap or neem oil. | Root rot: Repot in fresh soil and improve drainage.

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.

❓ Frequently Asked Questions — Comparing These Plants

Boston Fern

What are the light requirements for Boston Fern?

Boston Ferns prefer bright, indirect light. Direct sunlight can scorch the delicate fronds, causing them to turn brown and crispy. An east-facing window is ideal, providing gentle morning sunlight. A north-facing window can also work, but the plant may not grow as vigorously. If placing the fern near a south- or west-facing window, be sure to filter the light with a sheer curtain. Insufficient light can lead to leggy growth and pale fronds. Rotate the plant regularly to ensure even light exposure on all sides. Artificial grow lights can supplement natural light, especially during the darker winter months.

How do I care for Boston Fern?

Boston Ferns thrive in bright, indirect light and high humidity. Water consistently, keeping the soil evenly moist but not soggy. Check the soil moisture regularly and water when the top inch feels slightly dry. Mist the fronds frequently or place the plant on a pebble tray filled with water to increase humidity. Fertilize monthly during the growing season (spring and summer) with a diluted liquid fertilizer formulated for ferns. Avoid placing the plant in direct sunlight or near drafts, as these can cause the fronds to dry out and turn brown. Repot every 1-2 years in the spring, using a well-draining potting mix. Regularly remove any dead or yellowing fronds to encourage new growth and maintain the plant’s appearance. Monitor for pests such as spider mites and treat as needed.

How do I propagate Boston Fern?

Boston Ferns can be propagated by division or by spores. Division is the easier method. To divide, carefully remove the plant from its pot and gently separate the root ball into two or more sections, ensuring each section has healthy fronds and roots. Repot each section in fresh potting mix. Propagation by spores is more challenging. Collect spores from the underside of mature fronds and sow them on a moist, sterile potting mix. Cover with a clear plastic dome to maintain high humidity and keep in indirect light. Spores can take several weeks or months to germinate. Keep the soil consistently moist and provide adequate ventilation to prevent fungal growth.

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.

Last updated: April 25, 2026 — Plant care data reviewed and verified by our editorial team.