Cup Flower vs Heart Fern Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Cup Flower
Cobaea scandens
Cobaea scandens, commonly known as Cup Flower or Cup-and-Saucer Vine, is a vigorous, fast-growing perennial vine often grown as an annual in temperate climates. It is characterized by its climbing habit, using tendrils to attach to supports. The plant produces unique, bell-shaped flowers that start green and mature to a deep purple or white, resembling cups sitting on saucers. It is primarily an outdoor plant, valued for its rapid growth and ability to cover fences, trellises, and walls quickly. While occasionally grown indoors, it requires significant space and light to thrive.
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.
Quick Plant Comparison
| Feature | Cup Flower | Heart Fern |
|---|---|---|
| Light | Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours daily. | Bright, indirect light. Avoid direct sunlight, which can scorch the fronds. |
| Watering | Outdoors: Every 2-3 days in hot weather, less frequently in cooler weather. Indoors: Every 7-10 days, depending on light and humidity. | Every 3-5 days, depending on humidity and temperature |
| Humidity | 40-60% | 70-90% |
| Temperature | 18-27°C | 18-24°C |
| Care Level | Expert | Moderate |
| Growth Rate | Fast | Slow |
| Max Height | Outdoors: 6-12 meters. Indoors: 1-3 meters (highly dependent on support and pruning). | 6-12 inches |
| Pet Safety | ✅ Safe | ✅ Safe |
| Soil | Well-draining, fertile soil. A mix of potting soil, perlite, and compost is suitable. | Well-draining, moisture-retentive potting mix such as a mix of peat moss, perlite, and orchid bark. |
| Beginner Friendly | ❌ No | With Caution |
| Weekly Maintenance | 30 minutes weekly (pruning, watering, fertilizing). | 15 minutes weekly |
🔬 Botanical Information — Comparing These Plants
Cup Flower
| Scientific Name | Cobaea scandens |
|---|---|
| Family | Polemoniaceae |
| Native To | Mexico, Central America |
| Also Known As | Cup-and-Saucer Vine, Cathedral Bells, Mexican Ivy, Monastery Bells |
| Leaves | The leaves are pinnately compound, with 4-6 leaflets and a terminal tendril. The leaflets are ovate to elliptic, with a smooth margin and a dark green color. They are typically 5-10 cm long. |
| Flowers | It can flower indoors with sufficient light, but flowering is more prolific outdoors. The flowers are bell-shaped, about 5-7 cm in diameter, and start green before turning purple or white. They have a distinctive cup-and-saucer shape. |
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
Cup Flower
Heart Fern
🌱 Propagation — Comparing Plant Growth
Cup Flower
Methods: Seed, Stem cuttings
Difficulty: Moderate
Tips: For seeds, scarify the seed coat before sowing to improve germination. For stem cuttings, take semi-hardwood cuttings in late summer and root them in a well-draining medium.
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
Cup Flower
The cup-shaped flowers are its most distinctive feature, with their unique shape and color-changing properties. Its rapid growth rate allows it to quickly cover large areas, making it a popular choice for creating privacy screens or adding vertical interest to gardens.
- ✓ Provides quick coverage for fences and walls
- ✓ Attracts pollinators like bees and hummingbirds
- ✓ Adds a unique and exotic touch to the garden
- ✓ Offers a visually appealing display with its cup-shaped flowers
- ✓ Can be grown in containers, allowing for flexibility in placement
- 🐾 Pet Safe
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
Cup Flower
Heart Fern
🌞 Light Requirements
Cup Flower
Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours daily.
Low light tolerant: ❌ No
Heart Fern
Bright, indirect light. Avoid direct sunlight, which can scorch the fronds.
Low light tolerant: ❌ No
💧 Watering Needs
Cup Flower
Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Ensure good drainage. Indoors, allow the soil to dry out slightly between waterings. Signs of underwatering include wilting leaves; overwatering includes yellowing leaves and soggy soil.
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
Cup Flower
Temperature: 18-27°C
Humidity: 40-60%
Heart Fern
Temperature: 18-24°C
Humidity: 70-90%
🤔 Which Plant Is Right For You?
Cup Flower
Cobaea scandensGardeners with ample outdoor space looking for a fast-growing vine to cover structures.
✅ Choose This Plant If...
- You want a fast-growing vine to quickly cover a fence or trellis.
- You are looking for a plant with unique and interesting flowers.
- You want to attract pollinators to your garden.
- You have a sunny outdoor space where the vine can thrive.
- You enjoy a challenge and are willing to provide the specific care needed for indoor growth.
❌ Skip This Plant If...
- You have limited indoor space and cannot provide ample light.
- You are looking for a low-maintenance indoor plant.
- You live in a climate with harsh winters and don't want to overwinter the plant indoors.
Heart Fern
Hemionitis arifoliaExperienced 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.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Cup Flower is rated Expert care level, while Heart Fern is Moderate.
Cup Flower has fast growth, while Heart Fern grows slow.
💡 Pro Tips For Comparing These Plants
Cup Flower Care Tips
Cobaea scandens is primarily an outdoor plant. Growing it indoors is challenging due to its high light requirements and vigorous growth. It needs ample space, strong support, and regular pruning to manage its size. Providing adequate light is crucial for flowering indoors.
- Provide a strong support structure for the vine to climb.
- Water deeply but infrequently, allowing the soil to dry slightly between waterings.
- Fertilize regularly during the growing season to promote vigorous growth and flowering.
- Prune regularly to control size and shape, especially indoors.
- Monitor for pests and diseases and treat promptly.
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.
⚠️ Common Problems & Solutions — Plant Care Comparison
Cup Flower
Heart Fern
❓ Frequently Asked Questions — Comparing These Plants
Cup Flower
What are the light requirements for Cup Flower?
Cup Flower requires bright, indirect light to thrive and produce abundant blooms. A location near an east- or west-facing window is ideal, providing several hours of gentle morning or afternoon sun. Avoid placing the plant in direct, intense sunlight, which can scorch the leaves. If growing indoors, supplement natural light with a grow light if necessary, especially during the winter months. Insufficient light can result in leggy growth, fewer blooms, and pale foliage. Rotate the plant regularly to ensure even light exposure on all sides. When growing outdoors, choose a spot that receives full sun for at least 6 hours a day, but with some protection from the harshest midday rays, especially in hotter climates.
How do I care for Cup Flower?
Cup Flower thrives with consistent care. Provide bright, indirect light, avoiding harsh direct sunlight. Water thoroughly when the top inch of soil feels dry, ensuring good drainage to prevent root rot. Fertilize regularly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength, focusing on formulas higher in phosphorus to promote blooming. Maintain moderate humidity levels, especially indoors, by misting or using a humidifier. Prune spent flowers to encourage continuous blooming. Repot in spring every 1-2 years into a slightly larger pot with well-draining potting mix. Monitor for pests like aphids and spider mites, treating promptly with insecticidal soap or neem oil. Provide temperatures between 60-75°F (15-24°C) for optimal growth. Reduce watering and fertilization in the fall and winter as growth slows. Ensure good air circulation to prevent fungal diseases.
How do I propagate Cup Flower?
Cup Flower can be propagated through stem cuttings, division, and, less commonly, from keiki (small plantlets that grow on the parent plant). For stem cuttings, take 4-6 inch cuttings from healthy stems, remove the lower leaves, and dip the cut end in rooting hormone. Plant the cuttings in moist potting mix and cover with a plastic bag to maintain humidity. Keep in a warm, bright location until roots develop (usually 4-6 weeks). For division, carefully separate the root ball of a mature plant into smaller sections, ensuring each section has healthy roots and stems. Replant the divisions in separate pots. Keiki propagation is rare, but if keiki develop, allow them to grow until they have roots, then carefully remove them and plant in their own pots.
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 24, 2026 — Plant care data reviewed and verified by our editorial team.