Exacum vs Kalanchoe Plant Comparison

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

Exacum

Exacum

Exacum affine

VS
Kalanchoe

Kalanchoe

Kalanchoe blossfeldiana

Exacum

Exacum

Exacum affine

Exacum affine, commonly known as Persian Violet, is a small, bushy, herbaceous perennial often grown as an annual. It typically reaches a height of 15-30 cm. It features small, oval, glossy green leaves and a profusion of fragrant, star-shaped flowers, usually violet-blue, but also available in white, pink, and lavender. While technically a perennial, it is most often cultivated as an annual or a houseplant due to its sensitivity to cold temperatures. People grow it for its charming, long-lasting blooms and sweet fragrance.

Gentianaceae Socotra Island (Yemen)
✨ Features: Fragrant flowers, long blooming period
📖 Read Complete Exacum Guide
Kalanchoe

Kalanchoe

Kalanchoe blossfeldiana

Kalanchoe blossfeldiana is a popular succulent known for its vibrant and long-lasting flowers. It's a relatively small, bushy plant typically reaching about 12 inches in height and spread. The leaves are thick, scalloped, and dark green, providing a backdrop for clusters of small, brightly colored flowers that bloom in shades of red, pink, orange, yellow, and white. While often sold as an indoor plant, Kalanchoe thrives with ample sunlight and can be challenging to maintain indoors long-term without supplemental lighting. People grow it for its cheerful blooms and relatively easy care, though it can be tricky to rebloom indoors.

Crassulaceae Madagascar
✨ Features: Long-lasting blooms, succulent foliage.
📖 Read Complete Kalanchoe Guide

Quick Plant Comparison

Feature Exacum Kalanchoe
Light Bright, indirect light. Avoid direct sunlight, especially during the hottest part of the day. Bright, indirect light to full sun. Requires at least 6 hours of direct sunlight daily to promote flowering.
Watering Every 5-7 days, depending on environmental conditions Every 2-3 weeks, depending on environmental conditions.
Humidity 40-60% 30-50%
Temperature 18-21°C 18-24°C
Care Level Moderate Moderate
Growth Rate Moderate Slow
Max Height 15-30 cm 30 cm
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining potting mix, such as a mix of peat moss, perlite, and vermiculite. Well-draining succulent or cactus mix.
Beginner Friendly With Caution With Caution
Weekly Maintenance 10 minutes weekly 5 minutes weekly

🔬 Botanical Information — Comparing These Plants

Exacum

Scientific Name Exacum affine
Family Gentianaceae
Native To Socotra Island (Yemen)
Also Known As Persian Violet, German Violet, Arabian Violet, Tiny Violet
Leaves Small, oval, and glossy green leaves, typically 2-4 cm long. They have a smooth texture and are arranged oppositely along the stems.
Flowers Yes, it flowers indoors readily with proper care. The flowers are star-shaped, about 1-2 cm in diameter, and typically violet-blue, but can also be white, pink, or lavender. They have a sweet, noticeable fragrance.

Kalanchoe

Scientific Name Kalanchoe blossfeldiana
Family Crassulaceae
Native To Madagascar
Also Known As Florist Kalanchoe, Flaming Katy, Christmas Kalanchoe, Madagascar Widow's-thrill
Leaves The leaves are thick, fleshy, and oval-shaped with scalloped edges. They are typically dark green and have a slightly glossy texture. The leaves are approximately 5-7 cm long.
Flowers It flowers readily indoors if given sufficient light. The flowers are small, about 1 cm in diameter, and come in clusters of red, pink, orange, yellow, and white. The blooms can last for several weeks.

📏 Size & Growth — Plant Comparison

Exacum

Height 15-30 cm
Spread 15-25 cm
Growth Rate Moderate
Growth Pattern Bushy and compact, growing upright to a height of 15-30 cm. It does not trail or climb.

Kalanchoe

Height 30 cm
Spread 30 cm
Growth Rate Slow
Growth Pattern It grows in a bushy, upright habit, forming a compact mound of foliage. It does not spread aggressively.

🌱 Propagation — Comparing Plant Growth

Exacum

Methods: Seed, Stem cuttings

Difficulty: Moderate

Tips: For seeds, sow in spring. For stem cuttings, take cuttings in spring or summer and root in moist potting mix. Maintain high humidity.

Kalanchoe

Methods: Stem cuttings, Leaf cuttings

Difficulty: Easy

Tips: Allow cuttings to callous over for a few days before planting in well-draining soil. Keep the soil lightly moist until roots develop.

✨ Benefits & Features — Comparing Plant Value

Exacum

The intense fragrance of its small, star-shaped flowers is a standout feature. It is often grown as an annual, despite being a perennial, due to its specific environmental needs.

  • ✓ Adds a splash of color to indoor spaces.
  • ✓ Provides a pleasant fragrance.
  • ✓ Can improve mood and reduce stress.
  • ✓ Relatively compact size makes it suitable for small spaces.
  • ✓ Long blooming period provides extended enjoyment.
  • ⚠️ Toxic to pets

Kalanchoe

Kalanchoe blossfeldiana is known for its long-lasting and vibrant flowers, which can bloom for several weeks. Unlike some succulents, it is primarily grown for its floral display rather than its foliage.

  • ✓ Adds a pop of color to any room.
  • ✓ Relatively easy to care for.
  • ✓ Can be propagated easily.
  • ✓ Provides a sense of accomplishment when it reblooms.
  • ✓ Succulent foliage adds textural interest.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Exacum

Repotting Repot in spring if the plant becomes root-bound, typically every 1-2 years.
Pruning Pinch back stems to encourage bushier growth and remove spent flowers to prolong blooming.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-4 weeks during the growing season (spring and summer).
Seasonal Care During the growing season (spring and summer), water more frequently and fertilize regularly. Reduce watering in the fall and winter. Provide bright light year-round.

Kalanchoe

Repotting Every 1-2 years, or when the plant becomes root-bound.
Pruning Pinch back stems after flowering to encourage bushier growth. Remove any dead or yellowing leaves.
Fertilizing Balanced liquid fertilizer diluted to half strength, applied once in spring and once in summer.
Seasonal Care Reduce watering in winter during dormancy. Provide bright light year-round to encourage flowering.

🌞 Light Requirements

Exacum

Bright, indirect light. Avoid direct sunlight, especially during the hottest part of the day.

Low light tolerant: ❌ No

Kalanchoe

Bright, indirect light to full sun. Requires at least 6 hours of direct sunlight daily to promote flowering.

Low light tolerant: ❌ No

💧 Watering Needs

Exacum

Water thoroughly when the top inch of soil feels dry to the touch. Ensure good drainage to prevent root rot. Overwatering can lead to yellowing leaves and fungal diseases. Underwatering will cause wilting and bud drop.

Kalanchoe

Allow the soil to dry out completely between waterings. Overwatering can lead to root rot. Water thoroughly when the soil is dry to the touch, and then allow excess water to drain away. Signs of overwatering include yellowing leaves and soft, mushy stems. Underwatering will cause the leaves to shrivel and droop.

🌡️ Temperature & Humidity

Exacum

Temperature: 18-21°C

Humidity: 40-60%

Kalanchoe

Temperature: 18-24°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Exacum

Exacum

Exacum affine
Care: Moderate Time: 10 minutes weekly Beginner: With-caution

Someone who appreciates fragrant, flowering houseplants and is willing to provide the necessary care to maintain humidity and prevent overwatering.

✅ Choose This Plant If...

  • You love fragrant flowers and want a plant that blooms for a long time.
  • You can provide bright, indirect light and maintain moderate humidity.
  • You are attentive to watering needs and can avoid overwatering.
  • You enjoy the challenge of caring for a slightly more demanding houseplant.
  • You want a compact plant that fits well on a windowsill or small table.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You tend to overwater your plants.
  • You struggle to provide adequate humidity.
  • You prefer low-maintenance plants that tolerate neglect.
📍 Ideal Location: Bright windowsill (east or west-facing), bathroom with good light, or under grow lights.
🎨 Style: Cottagecore, Traditional, Romantic
🏠 Apartment Friendly: Yes
⚠️ According to the ASPCA, Exacum affine is toxic to dogs, cats, and horses. Symptoms include vomiting, diarrhea, and depression. All parts of the plant are considered toxic.
Kalanchoe

Kalanchoe

Kalanchoe blossfeldiana
Care: Moderate Time: 5 minutes weekly Beginner: With-caution

Someone looking for a colorful, low-maintenance succulent that can provide a burst of blooms, but who is aware of the toxicity to pets and can provide adequate light.

✅ Choose This Plant If...

  • You want a plant with long-lasting, vibrant flowers.
  • You are looking for a relatively low-maintenance succulent.
  • You have a very sunny windowsill or can provide supplemental lighting.
  • You want a plant that is easy to propagate.
  • You enjoy the challenge of encouraging a plant to rebloom.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You cannot provide bright light.
  • You tend to overwater your plants.
📍 Ideal Location: South-facing windowsill or under grow lights.
🎨 Style: Modern, Eclectic, Colorful
🏠 Apartment Friendly: Yes
⚠️ Toxic to dogs, cats, and horses. Contains cardiac glycosides. Symptoms include vomiting, diarrhea, weakness, and abnormal heart rhythm. All parts of the plant are toxic.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Neither - caution
Less Maintenance Similar effort
Apartment Friendly Both work!

⚡ Key Differences Between These Plants

📈

Exacum has moderate growth, while Kalanchoe grows slow.

💡 Pro Tips For Comparing These Plants

Exacum Care Tips

Exacum affine requires bright, indirect light, consistent moisture, and moderate humidity. It is sensitive to overwatering and cold drafts. Maintaining proper humidity is crucial for preventing bud drop. It is toxic to pets, so keep it out of reach.

  • Use a well-draining potting mix to prevent root rot.
  • Maintain moderate humidity by misting regularly or using a humidifier.
  • Avoid placing the plant in direct sunlight, which can scorch the leaves.
  • Pinch back stems to encourage bushier growth and more blooms.
  • Fertilize regularly during the growing season to promote flowering.
❄️ Winter: Reduce watering frequency as the plant's growth slows down. Maintain bright, indirect light. Avoid placing near cold drafts. Do not fertilize during the winter months.
☀️ Summer: Water more frequently during the warmer months. Ensure adequate humidity. Protect from direct sunlight to prevent leaf scorch. Fertilize regularly to promote flowering.

Kalanchoe Care Tips

Kalanchoe blossfeldiana is relatively easy to care for, but requires bright light to thrive and rebloom. Overwatering is a common problem. It's best suited for sunny windowsills or with supplemental lighting. Toxicity to pets is a significant concern.

  • Provide at least 6 hours of direct sunlight daily for optimal flowering.
  • Allow the soil to dry out completely between waterings to prevent root rot.
  • Fertilize sparingly, only during the growing season.
  • Pinch back stems after flowering to encourage bushier growth.
  • Reduce watering in winter during dormancy.
❄️ Winter: Reduce watering significantly during the winter months as the plant enters a period of dormancy. Maintain bright light conditions and avoid exposing the plant to temperatures below 10°C.
☀️ Summer: Provide adequate sunlight, but protect the plant from intense afternoon sun to prevent leaf burn. Water more frequently during the summer growing season, but still allow the soil to dry out between waterings.

⚠️ Common Problems & Solutions — Plant Care Comparison

Exacum

Common Issues: Bud drop, Root rot, Aphids, Spider mites
Solutions: Bud drop: Increase humidity and ensure consistent watering. | Root rot: Improve drainage and reduce watering frequency. | Aphids: Treat with insecticidal soap or neem oil. | Spider mites: Increase humidity and treat with miticide.

Kalanchoe

Common Issues: Root rot, Powdery mildew, Lack of flowering, Mealybugs
Solutions: Root rot: Improve drainage and reduce watering frequency. | Powdery mildew: Improve air circulation and treat with fungicide. | Lack of flowering: Provide more light and reduce watering after flowering. | Mealybugs: Treat with insecticidal soap or neem oil.

❓ Frequently Asked Questions — Comparing These Plants

Exacum

What are the light requirements for Exacum?

Exacum thrives in bright, indirect light. An east-facing window is ideal, providing gentle morning sun. Avoid direct sunlight, especially during the hottest part of the day, as it can burn the delicate leaves and fade the flowers. If you don’t have access to a bright window, consider using a grow light to supplement the natural light. Rotate the plant regularly to ensure even growth and blooming on all sides. Insufficient light can result in leggy growth and reduced flowering. If the leaves start to turn pale or yellow, it may be a sign of too much direct light.

How do I care for Exacum?

Exacum prefers bright, indirect light; direct sunlight can scorch the leaves. Water when the top inch of soil feels dry, ensuring proper drainage to prevent root rot. Maintain moderate humidity, ideally between 50-60%. Fertilize every 2-4 weeks during the blooming season with a balanced liquid fertilizer diluted to half strength. Keep temperatures between 60-75°F (15-24°C). Prune spent flowers to encourage continuous blooming. Repot only when necessary, using a well-draining potting mix. Avoid overwatering and provide good air circulation. Monitor for pests such as aphids or spider mites and treat promptly. Deadhead regularly. Provide a consistent environment to avoid stress. Ensure adequate drainage to prevent soggy soil.

How do I propagate Exacum?

Exacum can be propagated from stem cuttings. Take a 2-3 inch cutting from a healthy stem, removing the lower leaves. Dip the cut end in rooting hormone and plant in a well-draining potting mix. Keep the soil moist and provide bright, indirect light. Cover with a plastic bag to increase humidity. Roots should develop within a few weeks. Once rooted, transplant into a larger pot. Exacum is not typically propagated by division or keiki. Ensure the cutting is free from disease or pests. Mist regularly to maintain humidity during rooting. Provide bottom heat to encourage faster root development.

Kalanchoe

What are the light requirements for Kalanchoe?

Kalanchoe needs bright, indirect sunlight to thrive. Insufficient light can lead to leggy growth, faded colors, and a lack of blooms. A south-facing or east-facing window is ideal, providing several hours of bright light each day. If direct sunlight is too intense, filter it with a sheer curtain.

How do I care for Kalanchoe?

Kalanchoe thrives in bright, indirect sunlight. Water thoroughly only when the soil is completely dry, typically every 2-3 weeks, and ensure excellent drainage to prevent root rot. Use a well-draining succulent or cactus mix. Maintain temperatures between 60-85°F (15-29°C). Fertilize sparingly during the growing season (spring and summer) with a diluted balanced fertilizer.

How do I propagate Kalanchoe?

Kalanchoe is easily propagated through leaf cuttings, stem cuttings, or offsets. For leaf cuttings, allow the cut end to callous over for a few days before placing it on top of well-draining soil. Mist lightly and keep in a bright, indirect location.

Last updated: April 27, 2026 — Plant care data reviewed and verified by our editorial team.