Arum vs Cup Flower Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Arum
Arum italicum
Arum italicum is a tuberous herbaceous perennial known for its striking foliage and distinctive spadix and spathe flower structure. It emerges in the fall with arrow-shaped leaves, often beautifully veined in white or cream. The plant goes dormant in the summer. It is primarily an outdoor plant, thriving in woodland conditions. While it can be grown indoors, it requires very specific conditions to mimic its natural habitat. People grow it for its attractive foliage and unique flower structure.
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 | Arum | Cup Flower |
|---|---|---|
| Light | Partial to full shade outdoors. Indoors, requires very bright, indirect light, ideally a north-facing window or under grow lights. | Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours daily. |
| Watering | Every 10-14 days during growing season, much less frequently during dormancy. | Outdoors: Every 2-3 days in hot weather, less frequently in cooler weather. Indoors: Every 7-10 days, depending on light and humidity. |
| Humidity | 40-60% | 40-60% |
| Temperature | 10-21°C | 18-27°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Fast |
| Max Height | Indoors: 30-60 cm | Outdoors: 6-12 meters. Indoors: 1-3 meters (highly dependent on support and pruning). |
| Pet Safety | ❌ Toxic To Pets | ✅ Safe |
| Soil | Well-draining, humus-rich soil. A mix of potting soil, peat moss, and perlite is suitable. | Well-draining, fertile soil. A mix of potting soil, perlite, and compost is suitable. |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 15 minutes weekly during growing season, 5 minutes during dormancy. | 30 minutes weekly (pruning, watering, fertilizing). |
🔬 Botanical Information — Comparing These Plants
Arum
| Scientific Name | Arum italicum |
|---|---|
| Family | Araceae |
| Native To | Mediterranean region, from Portugal and Morocco to Turkey and Crimea |
| Also Known As | Italian Arum, Italian Lords-and-Ladies, Painted Arum |
| Leaves | The leaves are arrow-shaped, typically 20-30 cm long, and often feature prominent white or cream-colored veins. The texture is smooth and slightly waxy. |
| Flowers | Arum italicum produces a spadix and spathe flower structure. The spathe is a creamy-white or greenish-white hood-like structure that surrounds the spadix, a fleshy spike covered in tiny flowers. It rarely flowers 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
Arum
Cup Flower
🌱 Propagation — Comparing Plant Growth
Arum
Methods: Division of tubers, Seed
Difficulty: Moderate
Tips: Divide tubers in late summer or early fall. Sow seeds in the fall after the berries have ripened. Ensure good drainage when planting.
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
Arum
Arum italicum is unique for its winter foliage, which appears after most plants have lost their leaves. Its distinctive spadix and spathe flower structure also set it apart from other plants.
- ✓ Unique and striking appearance.
- ✓ Adds visual interest to shady areas.
- ✓ Can be a conversation starter.
- ✓ Provides a touch of the Mediterranean landscape.
- ✓ Offers a seasonal display of foliage and berries.
- ⚠️ 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
Arum
Cup Flower
🌞 Light Requirements
Arum
Partial to full shade outdoors. Indoors, requires very bright, indirect light, ideally a north-facing window or under grow lights.
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
Arum
Water thoroughly when the top inch of soil is dry during the growing season (fall to spring). Reduce watering significantly during dormancy (summer). Overwatering can lead to tuber rot. Underwatering will cause the leaves to wilt and brown.
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
Arum
Temperature: 10-21°C
Humidity: 40-60%
Cup Flower
Temperature: 18-27°C
Humidity: 40-60%
🤔 Which Plant Is Right For You?
Arum
Arum italicumExperienced gardeners who want a unique plant and can provide the specific conditions it needs.
✅ Choose This Plant If...
- You appreciate unique foliage and a striking plant structure.
- You can provide a cool, dormant period in the summer.
- You are an experienced gardener comfortable with challenging plants.
- You have a shady spot in your garden or can mimic those conditions indoors.
- You are prepared to handle a toxic plant and keep it away from pets and children.
❌ Skip This Plant If...
- You have pets or small children who might ingest the plant.
- You are a beginner gardener.
- You cannot provide a cool, dormant period.
- You don't have a bright, indirect light source.
- You prefer low-maintenance plants.
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
Arum has moderate growth, while Cup Flower grows fast.
💡 Pro Tips For Comparing These Plants
Arum Care Tips
Arum italicum is primarily an outdoor plant and requires expert care to thrive indoors. It needs specific light, temperature, and dormancy conditions. It is toxic to pets. Indoor cultivation is challenging due to its seasonal growth cycle and need for a cool, dormant period.
- Provide a cool, dry dormant period in the summer by reducing watering significantly and keeping the plant in a cooler location.
- Ensure excellent drainage to prevent tuber rot.
- Fertilize regularly during the growing season with a balanced liquid fertilizer.
- Monitor for pests like aphids and spider mites and treat promptly.
- Wear gloves when handling the plant to avoid skin irritation from the sap.
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
Arum
Cup Flower
❓ Frequently Asked Questions — Comparing These Plants
Arum
What are the light requirements for Arum?
Arum plants thrive best in bright, indirect light. Direct sunlight can scorch the leaves, so avoid placing them in areas with intense midday sun. An east-facing window is often ideal, providing gentle morning light. If you only have south or west-facing windows, filter the light with sheer curtains or blinds. Insufficient light can result in leggy growth and reduced flowering. Rotate the plant regularly to ensure even light exposure on all sides. During the darker months, consider supplementing with artificial grow lights to maintain healthy growth. Observe the plant’s foliage; if the leaves appear pale or stretched, it’s a sign that it needs more light.
How do I care for Arum?
Arum plants prefer bright, indirect light but can tolerate some shade. Water thoroughly when the top inch of soil feels dry to the touch, ensuring good drainage to prevent root rot. Fertilize monthly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Reduce watering and fertilization during the dormant period in fall and winter. Maintain moderate humidity, especially indoors. Repot every 1-2 years in spring, using a well-draining potting mix. Prune away any yellowing or dead leaves to encourage healthy growth. Protect from frost as Arum is not cold hardy. Monitor for pests such as aphids or spider mites and treat accordingly. Proper air circulation is essential to prevent fungal diseases.
How do I propagate Arum?
Arum can be propagated through division, stem cuttings, or from bulb offsets (keikis).
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: April 29, 2026 — Plant care data reviewed and verified by our editorial team.