Clarkia vs Heart Fern Plant Comparison

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

Clarkia

Clarkia

Clarkia unguiculata

VS
Heart Fern

Heart Fern

Hemionitis arifolia

Clarkia

Clarkia

Clarkia unguiculata

Clarkia unguiculata, also known as Elegant Clarkia or Mountain Garland, is an annual wildflower native to California. It typically grows to a height of 30-90 cm. It features slender stems and cup-shaped flowers with four petals, often in shades of pink, purple, or white. While it's a beautiful garden plant, it's primarily an outdoor species and not well-suited for indoor cultivation due to its high light requirements and need for air circulation. People grow it for its showy flowers and to attract pollinators to their gardens.

Onagraceae California, USA
✨ Features: Attracts pollinators, showy flowers
📖 Read Complete Clarkia Guide
Heart Fern

Heart Fern

Hemionitis arifolia

The Heart Fern, *Hemionitis arifolia*, is a small, epiphytic fern prized for its unique, heart-shaped fronds. It typically grows to a height of 6-12 inches. Unlike many ferns, it doesn't have traditional fern-like foliage; instead, it features glossy, dark green, heart-shaped leaves that arise from slender, wiry, black stems (petioles). It is primarily grown as an ornamental plant, especially in terrariums or as a houseplant, due to its distinctive appearance and relatively compact size. While it can be grown indoors, it requires specific conditions to thrive, making it a moderately challenging houseplant.

Pteridaceae Southeast Asia (Thailand, Malaysia)
✨ Features: Unique heart-shaped foliage
📖 Read Complete Heart Fern Guide

Quick Plant Comparison

Feature Clarkia Heart Fern
Light Full sun (at least 6-8 hours of direct sunlight daily) Bright, indirect light. Avoid direct sunlight, which can scorch the fronds.
Watering Every 2-3 days in hot weather, every 5-7 days in cooler weather, depending on soil drainage and sunlight exposure. Every 3-5 days, depending on humidity and temperature
Humidity 30-50% 70-90%
Temperature 15-24°C 18-24°C
Care Level Expert Moderate
Growth Rate Fast Slow
Max Height N/A (Outdoor plant, not suitable for indoor growing) 6-12 inches
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining soil, sandy loam is ideal Well-draining, moisture-retentive potting mix such as a mix of peat moss, perlite, and orchid bark.
Beginner Friendly ❌ No With Caution
Weekly Maintenance 5-10 minutes weekly (deadheading, watering) 15 minutes weekly

🔬 Botanical Information — Comparing These Plants

Clarkia

Scientific Name Clarkia unguiculata
Family Onagraceae
Native To California, USA
Also Known As Elegant Clarkia, Mountain Garland
Leaves The leaves are lance-shaped, alternate, and typically 2-7 cm long. They are a light green color and have smooth edges.
Flowers Does not flower indoors. Outdoors, it produces cup-shaped flowers with four petals, often in shades of pink, purple, or white. The flowers are approximately 2-5 cm in diameter and bloom in spring and summer.

Heart Fern

Scientific Name Hemionitis arifolia
Family Pteridaceae
Native To Southeast Asia (Thailand, Malaysia)
Also Known As Heart Fern
Leaves The leaves (fronds) are heart-shaped (cordate), glossy, and dark green. They are typically 1-2 inches in size and have a smooth texture. The petioles (stems) are slender, wiry, and black, providing a striking contrast to the green foliage.
Flowers Heart Ferns do not produce flowers. They reproduce via spores, which are found on the underside of the fronds in specialized structures called sporangia. Flowering is not a characteristic of ferns.

📏 Size & Growth — Plant Comparison

Clarkia

Height N/A (Outdoor plant, not suitable for indoor growing)
Spread N/A (Outdoor plant, not suitable for indoor growing)
Growth Rate Fast
Growth Pattern Upright, branching annual with slender stems.

Heart Fern

Height 6-12 inches
Spread 6-12 inches
Growth Rate Slow
Growth Pattern The Heart Fern grows in a clumping habit, with fronds arising from a central rhizome. It does not climb or trail, but rather forms a dense mound of heart-shaped leaves. It spreads slowly via rhizomes.

🌱 Propagation — Comparing Plant Growth

Clarkia

Methods: Seed

Difficulty: Easy

Tips: Sow seeds directly into the garden in early spring or fall. Lightly cover the seeds with soil and keep moist until germination.

Heart Fern

Methods: Spores, Division (of rhizomes)

Difficulty: Moderate

Tips: Propagating from spores is difficult and requires a sterile environment. Division can be done during repotting by carefully separating the rhizomes, ensuring each division has healthy fronds and roots. Plant the divisions in fresh potting mix and keep them consistently moist.

✨ Benefits & Features — Comparing Plant Value

Clarkia

Clarkia's cup-shaped flowers and slender stems create a delicate and elegant appearance. It is a California native wildflower, making it a great choice for native plant gardens. The flowers come in a variety of colors, including pink, purple, and white.

  • ✓ Attracts pollinators like bees and butterflies
  • ✓ Adds vibrant color to the garden
  • ✓ Provides a natural and informal aesthetic
  • ✓ Easy to grow from seed
  • ✓ Supports local ecosystems
  • ⚠️ Toxic to pets

Heart Fern

The Heart Fern is unique due to its heart-shaped fronds, which are unlike the typical fern foliage. It also reproduces via spores, a characteristic of ferns, but its overall appearance is quite distinct. Its small size and preference for high humidity make it a popular choice for terrariums.

  • ✓ Adds a unique aesthetic to your home.
  • ✓ Non-toxic to pets and children.
  • ✓ Can thrive in humid environments like bathrooms.
  • ✓ Relatively small and compact, fitting in various spaces.
  • ✓ Provides a calming and natural element to indoor spaces.
  • 🐾 Pet Safe

📅 Maintenance Schedule — Plant Care Comparison

Clarkia

Repotting N/A (Not applicable for outdoor annuals)
Pruning Deadhead spent flowers to encourage more blooms.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, applied every 4-6 weeks during the growing season.
Seasonal Care In spring, sow seeds directly into the garden. In summer, water regularly and deadhead spent flowers to encourage more blooms. In fall, collect seeds for next year's planting. In winter, the plant will die back.

Heart Fern

Repotting Repot every 1-2 years in the spring, or when the plant becomes root-bound.
Pruning Remove any dead or damaged fronds to maintain appearance and prevent disease.
Fertilizing Use a diluted (1/4 strength) balanced liquid fertilizer (e.g., 20-20-20) every 4-6 weeks during the growing season (spring and summer). Do not fertilize in the fall and winter.
Seasonal Care In winter, reduce watering frequency as growth slows. Maintain humidity levels. In summer, increase watering and ensure adequate ventilation.

🌞 Light Requirements

Clarkia

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

Low light tolerant: ❌ No

Heart Fern

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

Low light tolerant: ❌ No

💧 Watering Needs

Clarkia

Water regularly, especially during dry periods, to keep the soil consistently moist but not waterlogged. Allow the top inch of soil to dry out slightly between waterings. Overwatering can lead to root rot, while underwatering can cause wilting and reduced flowering.

Heart Fern

Keep the soil consistently moist but not waterlogged. Allow the top inch of soil to slightly dry out before watering again. Overwatering can lead to root rot, while underwatering can cause the fronds to dry and crisp. Use distilled or filtered water to avoid mineral buildup.

🌡️ Temperature & Humidity

Clarkia

Temperature: 15-24°C

Humidity: 30-50%

Heart Fern

Temperature: 18-24°C

Humidity: 70-90%

🤔 Which Plant Is Right For You?

Clarkia

Clarkia

Clarkia unguiculata
Care: Expert Time: 5-10 minutes weekly (deadheading, watering) Beginner: No

Gardeners looking to add vibrant color and attract pollinators to their outdoor spaces.

✅ Choose This Plant If...

  • You want to attract pollinators to your garden.
  • You love vibrant, colorful wildflowers.
  • You have a sunny garden space.
  • You enjoy easy-to-grow annuals.
  • You want to create a cottage garden aesthetic.

❌ Skip This Plant If...

  • You only have indoor growing space.
  • You are looking for a low-maintenance houseplant.
  • You have pets that might ingest the plant.
📍 Ideal Location: Outdoor garden, wildflower meadow
🎨 Style: Cottagecore, Bohemian, Naturalistic
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Clarkia species contain cucurbitacins which are toxic to dogs, cats, and horses. Symptoms include gastrointestinal upset (vomiting, diarrhea), and dermatitis.
Heart Fern

Heart Fern

Hemionitis arifolia
Care: Moderate Time: 15 minutes weekly Beginner: With-caution

Experienced plant enthusiasts who can provide high humidity and consistent moisture.

✅ Choose This Plant If...

  • You love unique foliage and are willing to provide high humidity.
  • You have experience with other humidity-loving plants.
  • You want a small, compact plant for a terrarium or bright bathroom.
  • You are looking for a non-toxic plant for a home with pets.
  • You enjoy a plant that requires a bit more attention and care.

❌ Skip This Plant If...

  • You struggle to maintain consistent watering schedules.
  • You live in a dry climate and cannot provide adequate humidity.
  • You are a beginner plant owner looking for a low-maintenance plant.
📍 Ideal Location: Bright bathroom, kitchen with good humidity, or a terrarium.
🎨 Style: Tropical, Bohemian, Eclectic
🏠 Apartment Friendly: Yes
⚠️ According to the ASPCA, *Hemionitis arifolia* is not listed as toxic to dogs, cats, or horses.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Heart Fern ✓
Less Maintenance Similar effort
Apartment Friendly Heart Fern

⚡ Key Differences Between These Plants

🎯

Clarkia is rated Expert care level, while Heart Fern is Moderate.

📈

Clarkia has fast growth, while Heart Fern grows slow.

💡 Pro Tips For Comparing These Plants

Clarkia Care Tips

Clarkia is an outdoor plant that requires full sun and well-draining soil. It's not suitable for indoor growing due to its high light and air circulation needs. Attempting to grow it indoors will likely result in leggy growth, poor flowering, and susceptibility to pests and diseases.

  • Sow seeds directly into the garden in early spring or fall for best results.
  • Ensure well-draining soil to prevent root rot.
  • Water regularly, especially during dry periods.
  • Deadhead spent flowers to encourage more blooms.
  • Provide full sun for optimal flowering.
❄️ Winter: The plant is an annual and will die back in winter. Collect seeds for next year's planting.
☀️ Summer: Water regularly, especially during dry periods. Deadhead spent flowers to encourage more blooms. Provide full sun for optimal flowering.

Heart Fern Care Tips

Heart Ferns require high humidity and consistent moisture to thrive indoors. They are not as forgiving as some other ferns and can be challenging for beginners. Maintaining proper humidity is crucial for their survival.

  • Use distilled or rainwater to avoid mineral buildup on the fronds.
  • Maintain high humidity by using a humidifier, pebble tray, or grouping plants together.
  • Avoid placing the plant near drafts or heating vents.
  • Monitor for pests regularly and treat promptly.
  • Provide adequate air circulation to prevent fungal diseases.
❄️ Winter: Reduce watering frequency as growth slows during the winter months. Maintain humidity levels and avoid placing the plant near cold drafts. Do not fertilize during the winter.
☀️ Summer: Increase watering frequency during the summer months as the plant actively grows. Ensure adequate ventilation to prevent fungal diseases. Protect from direct sunlight to prevent scorching.

⚠️ Common Problems & Solutions — Plant Care Comparison

Clarkia

Common Issues: Powdery mildew, aphids, root rot
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Aphids: Spray with insecticidal soap. Root rot: Ensure well-draining soil and avoid overwatering.

Heart Fern

Common Issues: Browning fronds, root rot, pest infestations (scale, mealybugs)
Solutions: Browning fronds: Increase humidity. Root rot: Improve drainage and reduce watering frequency. Pests: Treat with insecticidal soap or neem oil.

❓ Frequently Asked Questions — Comparing These Plants

Clarkia

What are the light requirements for Clarkia?

Clarkia requires at least six hours of direct sunlight per day to thrive and produce abundant blooms. In hotter climates, some afternoon shade can be beneficial to prevent scorching of the delicate petals. When grown indoors, place Clarkia near a south-facing window where it can receive ample sunlight. Rotate the plant regularly to ensure even light exposure on all sides. Insufficient light can result in leggy growth and reduced flowering. Supplemental lighting, such as grow lights, can be used to provide additional light, especially during the shorter days of winter.

How do I care for Clarkia?

Clarkia thrives in well-draining soil and prefers full sun to partial shade. Water regularly, especially during dry periods, but avoid overwatering to prevent root rot. Fertilize lightly with a balanced fertilizer every few weeks during the growing season to promote abundant blooms. Deadhead spent flowers to encourage continuous flowering and prevent seed formation if self-seeding is not desired. Clarkia prefers cooler temperatures and can tolerate light frost. Protect from strong winds to prevent stems from breaking. Provide support for taller varieties to prevent them from flopping over. Monitor for pests such as aphids and treat as needed. Ensure good air circulation to prevent fungal diseases.

How do I propagate Clarkia?

Clarkia is typically propagated by seed. Direct sow seeds in the garden in early spring or fall. For earlier blooms, start seeds indoors 6-8 weeks before the last frost. Sow seeds thinly on the surface of well-draining soil and lightly cover with soil. Keep the soil moist until germination occurs, which usually takes 7-14 days. Thin seedlings to allow for adequate spacing. Clarkia can also self-seed readily in the garden. However, other propagation methods like division or stem cuttings are generally not used for Clarkia due to its growth habit and life cycle. Focus on seed saving for future planting seasons.

Heart Fern

What are the light requirements for Heart Fern?

Heart Ferns thrive in bright, indirect light. Direct sunlight can easily scorch their delicate fronds, causing them to turn brown or yellow. An east-facing window is often ideal, providing gentle morning sunlight. A north-facing window can also work, but ensure the plant receives sufficient light. Avoid placing the fern in a south- or west-facing window without adequate shading. If the leaves start to pale or the plant appears leggy, it may not be receiving enough light. In such cases, consider moving it to a brighter location or supplementing with artificial light. Grow lights can be particularly helpful during the darker winter months. Remember to rotate the plant periodically to ensure even light exposure on all sides.

How do I care for Heart Fern?

Heart Ferns require consistent moisture and high humidity to thrive. Keep the soil consistently moist but not soggy. Water when the top inch of soil feels slightly dry. Use filtered or rainwater to avoid mineral buildup. Place the fern in a location with bright, indirect light; direct sunlight can scorch the delicate fronds. Maintain humidity levels above 60% by using a humidifier, pebble tray, or grouping plants together. The ideal temperature range is between 65°F and 75°F (18°C to 24°C). Fertilize sparingly during the growing season (spring and summer) with a diluted liquid fertilizer formulated for ferns. Repot every 1-2 years into a slightly larger pot with a well-draining potting mix suitable for ferns. Prune any yellowing or damaged fronds to encourage new growth. Regularly check for pests such as mealybugs or scale and treat promptly if detected. Ensure good air circulation to prevent fungal diseases. Mist the plant regularly to maintain humidity.

How do I propagate Heart Fern?

Heart Fern can be propagated through division or spores. Division is the easier method. During repotting, carefully separate the rhizomes into smaller clumps, ensuring each clump has healthy roots and fronds. Plant each clump in its own pot with well-draining potting mix. Keep the soil consistently moist and maintain high humidity. Propagating from spores is more challenging and requires a sterile environment. Collect spores from mature fronds and sow them on a sterile growing medium. Cover with a humidity dome and maintain consistent moisture and warmth. It can take several months for spores to germinate and develop into small plantlets. Once the plantlets are large enough to handle, transplant them into individual pots. Both methods require patience and attention to detail.

Last updated: April 22, 2026 — Plant care data reviewed and verified by our editorial team.