Crepe Myrtle vs Cup Flower Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Crepe Myrtle
Lagerstroemia indica
Crepe Myrtles are deciduous trees or large shrubs known for their vibrant summer flowers, attractive peeling bark, and colorful fall foliage. They typically grow to heights of 15-25 feet outdoors, though dwarf varieties exist. The flowers come in shades of pink, red, white, and purple, with a crinkled, crepe-like texture. They are primarily grown as ornamental trees in gardens and landscapes for their year-round visual interest. Due to their high light requirements and large size, they are not suitable for indoor growing.
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.
Quick Plant Comparison
| Feature | Crepe Myrtle | Cup Flower |
|---|---|---|
| Light | Full sun (at least 6-8 hours of direct sunlight per day) | Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours daily. |
| Watering | Outdoors: Once or twice a week during the growing season, less frequently during dormancy. Indoors (not recommended): Would need very frequent watering due to high light needs. | Outdoors: Every 2-3 days in hot weather, less frequently in cooler weather. Indoors: Every 7-10 days, depending on light and humidity. |
| Humidity | 30-50% | 40-60% |
| Temperature | 18-32°C | 18-27°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Fast |
| Max Height | Not suitable for indoor growing; outdoors: 4.5-7.5 meters (15-25 feet) | Outdoors: 6-12 meters. Indoors: 1-3 meters (highly dependent on support and pruning). |
| Pet Safety | ❌ Toxic To Pets | ✅ Safe |
| Soil | Well-draining, slightly acidic soil | Well-draining, fertile soil. A mix of potting soil, perlite, and compost is suitable. |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 30 minutes monthly (pruning, fertilizing, pest control) | 30 minutes weekly (pruning, watering, fertilizing). |
🔬 Botanical Information — Comparing These Plants
Crepe Myrtle
| Scientific Name | Lagerstroemia indica |
|---|---|
| Family | Lythraceae |
| Native To | Native to China and Korea |
| Also Known As | Crepe Myrtle, Crape Myrtle |
| Leaves | The leaves are small, oval-shaped, and dark green in summer, turning to shades of yellow, orange, and red in the fall. They are arranged oppositely or alternately on the branches. |
| Flowers | Crepe Myrtles produce large clusters of crinkled, crepe-like flowers in summer. The flowers come in shades of pink, red, white, and purple. They do not flower indoors. |
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. |
📏 Size & Growth — Plant Comparison
Crepe Myrtle
Cup Flower
🌱 Propagation — Comparing Plant Growth
Crepe Myrtle
Methods: Stem cuttings, Seed
Difficulty: Moderate
Tips: Take softwood cuttings in late spring or early summer. Dip in rooting hormone and plant in well-draining soil. Keep moist and warm. Seeds can be sown in spring after stratification.
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.
✨ Benefits & Features — Comparing Plant Value
Crepe Myrtle
Crepe Myrtles are known for their long blooming period and attractive peeling bark. The flowers have a unique, crepe-like texture, giving the tree its common name.
- ✓ Provides beautiful summer flowers
- ✓ Offers year-round visual interest with attractive bark and fall color
- ✓ Attracts pollinators to the garden
- ✓ Provides shade in the summer
- ✓ Relatively low-maintenance once established
- ⚠️ Toxic to pets
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
📅 Maintenance Schedule — Plant Care Comparison
Crepe Myrtle
Cup Flower
🌞 Light Requirements
Crepe Myrtle
Full sun (at least 6-8 hours of direct sunlight per day)
Low light tolerant: ❌ No
Cup Flower
Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours daily.
Low light tolerant: ❌ No
💧 Watering Needs
Crepe Myrtle
Water deeply when the top few inches of soil are dry. Avoid overwatering, which can lead to root rot. Signs of underwatering include wilting leaves and stunted growth. Signs of overwatering include yellowing leaves and soggy soil.
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.
🌡️ Temperature & Humidity
Crepe Myrtle
Temperature: 18-32°C
Humidity: 30-50%
Cup Flower
Temperature: 18-27°C
Humidity: 40-60%
🤔 Which Plant Is Right For You?
Crepe Myrtle
Lagerstroemia indicaGardeners with sunny outdoor spaces who want a beautiful, flowering tree with year-round interest.
✅ Choose This Plant If...
- You want a tree with stunning summer blooms.
- You appreciate year-round visual interest with attractive bark and fall color.
- You have a sunny outdoor space.
- You are looking for a relatively low-maintenance tree once established.
- You want to attract pollinators to your garden.
❌ Skip This Plant If...
- You have limited sunlight.
- You are looking for an indoor plant.
- You have pets that might ingest the plant.
- You live in a very cold climate where the tree may not thrive.
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.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Crepe Myrtle has moderate growth, while Cup Flower grows fast.
💡 Pro Tips For Comparing These Plants
Crepe Myrtle Care Tips
Crepe Myrtles are outdoor trees that require full sun and well-draining soil. They are not suitable for indoor growing due to their high light requirements and large size. Attempting to grow them indoors will likely result in a weak, unhealthy plant.
- Plant in well-draining soil to prevent root rot.
- Provide full sun for optimal flowering.
- Prune in late winter or early spring to remove dead or crossing branches.
- Fertilize in spring and early summer with a balanced fertilizer.
- Monitor for pests and diseases and treat promptly.
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.
⚠️ Common Problems & Solutions — Plant Care Comparison
Crepe Myrtle
Cup Flower
❓ Frequently Asked Questions — Comparing These Plants
Crepe Myrtle
What are the light requirements for Crepe Myrtle?
Indoor Crepe Myrtles require bright, indirect light to thrive and produce their signature blooms. A south- or west-facing window is ideal, providing several hours of sunlight daily. If natural light is insufficient, supplement with grow lights. Rotate the plant regularly to ensure even light exposure on all sides. Avoid placing the Crepe Myrtle in direct sunlight, which can scorch the leaves. Signs of insufficient light include leggy growth, pale leaves, and a lack of flowering. During the winter months, when light levels are lower, consider providing additional artificial light to support healthy growth.
How do I care for Crepe Myrtle?
To ensure your indoor Crepe Myrtle thrives, provide bright, indirect light, ideally from a south- or west-facing window. Water thoroughly when the top inch of soil feels dry, ensuring proper drainage to prevent root rot. Maintain a moderate humidity level by misting the foliage regularly or using a humidifier. Fertilize during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Prune in late winter or early spring to remove dead or crossing branches and to shape the plant. Repot every two to three years into a slightly larger pot with well-draining potting mix. Monitor for pests such as aphids or spider mites and treat promptly. Maintain stable temperatures between 65-75°F (18-24°C).
How do I propagate Crepe Myrtle?
Crepe Myrtles can be propagated through stem cuttings or air layering. For stem cuttings, take a 4-6 inch cutting from new growth in the spring or summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cutting in a well-draining potting mix and keep it moist in a humid environment until roots develop. For air layering, make a small incision on a stem, apply rooting hormone, and wrap the area with moist sphagnum moss. Cover the moss with plastic wrap and secure it tightly. Once roots develop, cut the stem below the wrapped area and plant it in a pot. Rooting can take several weeks to a few months. Maintain consistent moisture.
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.
Last updated: May 16, 2026 — Plant care data reviewed and verified by our editorial team.