Crown of Thorns vs Honesty Plant Comparison

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

Crown of Thorns

Crown of Thorns

Euphorbia milii

VS
Honesty

Honesty

Lunaria annua

Crown of Thorns

Crown of Thorns

Euphorbia milii

Euphorbia milii, commonly known as Crown of Thorns, is a succulent shrub characterized by its thorny stems and vibrant bracts surrounding small, inconspicuous flowers. Native to Madagascar, it is a popular ornamental plant grown for its drought tolerance and long-lasting blooms. It typically grows as a sprawling shrub, reaching up to 1-2 meters in height. While it can be grown indoors, it thrives best with ample sunlight, often making it more suitable as an outdoor plant in warmer climates. People grow it for its unique appearance and relatively easy care.

Euphorbiaceae Madagascar
✨ Features: Long-lasting blooms, drought tolerance
📖 Read Complete Crown of Thorns Guide
Honesty

Honesty

Lunaria annua

Lunaria annua, commonly known as Honesty, is a biennial plant often grown as an annual. It features heart-shaped, toothed leaves and produces clusters of fragrant, purple or white flowers in spring and summer. The plant is most prized for its distinctive, translucent, papery seedpods that resemble silver coins, hence the common names. It typically grows to a height of 60-90 cm (2-3 feet). While primarily an outdoor plant, it's grown for its ornamental seedpods, which are often dried and used in floral arrangements. It is not naturally an indoor plant and will struggle in typical indoor conditions.

Brassicaceae Southeastern Europe and Western Asia
✨ Features: Ornamental seedpods, fragrant flowers
📖 Read Complete Honesty Guide

Quick Plant Comparison

Feature Crown of Thorns Honesty
Light Requires at least 4-6 hours of direct sunlight daily. Insufficient light will result in leggy growth and reduced flowering. Full sun to partial shade
Watering Every 2-3 weeks, depending on environmental conditions and pot size. Every 7-10 days outdoors, depending on rainfall and temperature
Humidity 30-50% 40-60%
Temperature 18-27°C 15-25°C
Care Level Moderate Expert
Growth Rate Slow Fast
Max Height 0.3-0.6 meters (indoors) N/A (primarily grown outdoors)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining succulent or cactus mix Well-draining soil, such as a mix of garden soil, compost, and perlite
Beginner Friendly With Caution ❌ No
Weekly Maintenance 10 minutes weekly 10 minutes weekly (weeding, watering)

🔬 Botanical Information — Comparing These Plants

Crown of Thorns

Scientific Name Euphorbia milii
Family Euphorbiaceae
Native To Madagascar
Also Known As Crown of Thorns, Christ Plant, Christ Thorn
Leaves The leaves are small, oval-shaped, and typically bright green. They are deciduous, meaning they may drop off during periods of stress or dormancy, especially in winter.
Flowers It can flower indoors, but flowering is more prolific with ample sunlight. The true flowers are small and inconspicuous, surrounded by colorful bracts that can be red, pink, yellow, or white.

Honesty

Scientific Name Lunaria annua
Family Brassicaceae
Native To Southeastern Europe and Western Asia
Also Known As Honesty, Silver Dollar Plant, Money Plant, Moonwort
Leaves Heart-shaped, toothed leaves that are typically 5-15 cm (2-6 inches) long. The leaves are medium green and have a slightly rough texture.
Flowers Produces clusters of fragrant, purple or white flowers in spring and summer. The flowers are small, about 2 cm (0.75 inches) in diameter, and have four petals.

📏 Size & Growth — Plant Comparison

Crown of Thorns

Height 0.3-0.6 meters (indoors)
Spread 0.3-0.5 meters
Growth Rate Slow
Growth Pattern The plant grows as an upright, branching shrub with thick, thorny stems. It can become somewhat sprawling as it matures, especially if not pruned regularly.

Honesty

Height N/A (primarily grown outdoors)
Spread 30-60 cm (1-2 feet)
Growth Rate Fast
Growth Pattern Upright, branching plant that typically grows to a height of 60-90 cm (2-3 feet). It forms a bushy habit with multiple stems emerging from the base.

🌱 Propagation — Comparing Plant Growth

Crown of Thorns

Methods: Stem cuttings

Difficulty: Easy

Tips: Allow the cut end to callus over for a few days before planting in well-draining soil. Use rooting hormone for better success.

Honesty

Methods: Seed

Difficulty: Easy

Tips: Sow seeds directly into the garden in spring or fall. Seeds can also be started indoors 6-8 weeks before the last frost. Ensure good soil contact and keep the soil moist until germination.

✨ Benefits & Features — Comparing Plant Value

Crown of Thorns

The Crown of Thorns is unique due to its thorny stems and the colorful bracts that surround its small flowers. Unlike many flowering plants, the bracts provide color for extended periods, making it a long-lasting ornamental plant.

  • ✓ Drought tolerance makes it easy to care for
  • ✓ Long-lasting blooms add color to your space
  • ✓ Unique appearance provides visual interest
  • ✓ Can tolerate neglect, making it suitable for busy individuals
  • ✓ Adds a touch of history and symbolism to your plant collection
  • ⚠️ Toxic to pets

Honesty

The translucent, papery seedpods are its most distinctive feature, giving it the common name 'Silver Dollar Plant'. The plant's ability to self-seed readily allows for natural propagation and a continuous display in the garden. Its fragrant flowers attract pollinators, contributing to garden biodiversity.

  • ✓ Provides ornamental seedpods for dried arrangements.
  • ✓ Attracts pollinators to the garden.
  • ✓ Adds visual interest to the garden in fall and winter.
  • ✓ Low-maintenance once established.
  • ✓ Fragrant flowers enhance the garden experience.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Crown of Thorns

Repotting Every 2-3 years, or when the plant becomes root-bound.
Pruning Prune to maintain shape and remove dead or damaged stems. Wear gloves to avoid skin irritation from the sap.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, applied every 2-3 months during the growing season (spring/summer).
Seasonal Care Reduce watering in winter. Provide bright light year-round. Protect from frost.

Honesty

Repotting N/A (primarily grown outdoors)
Pruning Cut back the plant after flowering to encourage seedpod production. Remove any dead or damaged foliage.
Fertilizing Balanced fertilizer (10-10-10) during the growing season (spring and summer), diluted to half strength, every 4-6 weeks.
Seasonal Care In spring, sow seeds or transplant seedlings. Water regularly during the growing season. In fall, allow seedpods to dry on the plant before harvesting. Cut back the plant after seedpods are harvested.

🌞 Light Requirements

Crown of Thorns

Requires at least 4-6 hours of direct sunlight daily. Insufficient light will result in leggy growth and reduced flowering.

Low light tolerant: ❌ No

Honesty

Full sun to partial shade

Low light tolerant: ❌ No

💧 Watering Needs

Crown of Thorns

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. Signs of overwatering include yellowing leaves and stem rot. Underwatering will cause leaf drop and shriveling.

Honesty

Water regularly, especially during dry periods. Avoid overwatering, which can lead to root rot. Allow the soil to dry slightly between waterings. Signs of underwatering include wilting leaves, while overwatering can cause yellowing and leaf drop.

🌡️ Temperature & Humidity

Crown of Thorns

Temperature: 18-27°C

Humidity: 30-50%

Honesty

Temperature: 15-25°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Crown of Thorns

Crown of Thorns

Euphorbia milii
Care: Moderate Time: 10 minutes weekly Beginner: With-caution

Experienced plant owners who can provide bright light and are aware of the plant's toxicity.

✅ Choose This Plant If...

  • You want a drought-tolerant plant that flowers for a long period.
  • You have a sunny location where the plant can thrive.
  • You are experienced with caring for succulents and understand their watering needs.
  • You are looking for a unique and interesting plant with a historical connection.
  • You can keep the plant away from pets and children due to its toxicity.

❌ Skip This Plant If...

  • You have pets or small children who might ingest the plant.
  • You cannot provide adequate sunlight.
  • You tend to overwater plants.
  • You are looking for a low-maintenance plant that thrives in low-light conditions.
📍 Ideal Location: South-facing window or sunny patio
🎨 Style: Desert, Southwestern, Eclectic
🏠 Apartment Friendly: Limited
⚠️ All parts of the plant contain a milky sap that is toxic to dogs, cats, and horses. Symptoms include oral irritation, vomiting, diarrhea, and skin irritation upon contact. According to the ASPCA, ingestion can cause gastrointestinal upset and skin irritation.
Honesty

Honesty

Lunaria annua
Care: Expert Time: 10 minutes weekly (weeding, watering) Beginner: No

Gardeners who want to add unique, ornamental seedpods to their garden and dried flower arrangements.

✅ Choose This Plant If...

  • You love unique dried flower arrangements and want to grow your own materials.
  • You have a sunny garden spot and enjoy cottage-style gardens.
  • You want to attract pollinators to your garden with its fragrant flowers.
  • You enjoy the sound of rustling seedpods in the breeze.
  • You want a low-maintenance plant that adds visual interest to your garden in the fall and winter.

❌ Skip This Plant If...

  • You have pets that might ingest the plant, as it is toxic.
  • You don't have a sunny outdoor space.
  • You are looking for a plant that thrives indoors.
📍 Ideal Location: Outdoor garden or flower bed with full sun exposure
🎨 Style: Cottage, Rustic, Traditional
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Honesty is toxic to dogs, cats, and horses. The toxic principle is unknown. Symptoms include oral irritation, salivation, vomiting, and diarrhea.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Neither - caution
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

🎯

Crown of Thorns is rated Moderate care level, while Honesty is Expert.

📈

Crown of Thorns has slow growth, while Honesty grows fast.

💡 Pro Tips For Comparing These Plants

Crown of Thorns Care Tips

Crown of Thorns requires bright sunlight and well-draining soil. Overwatering is a common issue. It can be grown indoors with sufficient light, but may not flower as profusely as when grown outdoors. Toxicity to pets is a significant concern.

  • Provide at least 4-6 hours of direct sunlight daily for optimal growth and flowering.
  • Allow the soil to dry out completely between waterings to prevent root rot.
  • Use a well-draining succulent or cactus mix to ensure proper drainage.
  • Fertilize sparingly during the growing season with a balanced liquid fertilizer.
  • Wear gloves when pruning or handling the plant to avoid skin irritation from the sap.
❄️ Winter: Reduce watering significantly during the winter months. Ensure the plant receives as much sunlight as possible. Protect from frost.
☀️ Summer: Water more frequently during the summer growing season, but still allow the soil to dry out between waterings. Provide adequate ventilation to prevent fungal diseases.

Honesty Care Tips

Honesty is primarily an outdoor plant and is challenging to grow indoors due to its high light requirements. It needs full sun to thrive and produce abundant seedpods. Indoor cultivation is not recommended unless you can provide very bright light and proper ventilation.

  • Allow seedpods to dry on the plant before harvesting for best results.
  • Provide well-draining soil to prevent root rot.
  • Water regularly during dry periods, especially when plants are young.
  • Deadhead spent flowers to encourage more seedpod production.
  • Protect from strong winds, which can damage the seedpods.
❄️ Winter: In colder climates, the plant may die back to the ground in winter. Mulch around the base of the plant to protect the roots. Allow seedpods to remain on the plant for winter interest.
☀️ Summer: Water regularly during dry periods. Provide some afternoon shade in hot climates to prevent leaf scorch. Monitor for pests and diseases and treat as needed.

⚠️ Common Problems & Solutions — Plant Care Comparison

Crown of Thorns

Common Issues: Root rot, spider mites, mealybugs, leaf drop
Solutions: Root rot: Improve drainage, reduce watering frequency. Spider mites: Insecticidal soap or neem oil. Mealybugs: Isopropyl alcohol or insecticidal soap. Leaf drop: Adjust watering and light levels.

Honesty

Common Issues: Powdery mildew, leaf spot, aphids, slugs
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Leaf spot: Remove affected leaves and apply a fungicide. Aphids: Spray with insecticidal soap. Slugs: Use slug bait or handpick them off the plants.

❓ Frequently Asked Questions — Comparing These Plants

Crown of Thorns

What are the light requirements for Crown of Thorns?

Crown of Thorns requires bright, direct sunlight to thrive. Ideally, place it in a south-facing window where it can receive at least 4-6 hours of sunlight per day. Insufficient light can lead to leggy growth, reduced flowering, and a loss of vibrancy in the bracts. If you don’t have a sufficiently sunny window, consider supplementing with a grow light. Rotate the plant regularly to ensure even light exposure on all sides. During the summer months, you can move your Crown of Thorns outdoors to a sunny location, but be sure to acclimate it gradually to avoid sunburn. The plant’s ability to flower profusely depends on adequate light.

How do I care for Crown of Thorns?

Crown of Thorns thrives on neglect, making it an easy-care succulent. Plant it in well-draining soil, such as a cactus mix, to prevent root rot. Provide it with bright, direct sunlight for at least 4-6 hours daily. Water sparingly, allowing the soil to dry completely between waterings. Reduce watering frequency during the dormant winter months. Fertilize lightly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Maintain a room temperature between 65-75°F (18-24°C). Avoid overwatering, as this is the most common cause of problems. Repot every 2-3 years, or when the plant becomes root-bound. Prune to maintain shape and remove dead or damaged stems. Be cautious of the milky sap, which can be irritating to the skin and eyes.

How do I propagate Crown of Thorns?

Crown of Thorns can be propagated through stem cuttings. Allow the cut end to callous over for several days before planting in well-draining soil. Keep the soil slightly moist until roots develop. Leaf cuttings are not generally successful. Offsets, or small plantlets that grow at the base of the plant, can be carefully separated and potted individually. Wear gloves to protect your skin from the irritating sap. Rooting hormone can improve the success rate of stem cuttings. Provide bright, indirect light during the rooting process. Avoid overwatering, as this can lead to rot. Propagation is best done during the growing season (spring and summer).

Honesty

What are the light requirements for Honesty?

Honesty prefers partial shade, especially in hotter climates. While it can tolerate full sun, too much direct sunlight can scorch the leaves and fade the flowers. In cooler regions, Honesty can thrive in full sun, but afternoon shade is still beneficial. When grown indoors, place Honesty near a bright, east-facing window that receives morning sun. Avoid south-facing windows that provide intense afternoon sun. If you don’t have access to natural light, you can supplement with artificial grow lights. Ensure the lights are positioned about 12-18 inches above the plant and provide at least 14-16 hours of light per day. Insufficient light can lead to leggy growth and reduced flowering.

How do I care for Honesty?

Honesty is relatively easy to care for, making it a great choice for beginner gardeners. It thrives in well-draining soil and prefers partial shade, although it can tolerate full sun in cooler climates. Water regularly, especially during dry periods, but avoid overwatering, which can lead to root rot. Fertilize sparingly, using a balanced fertilizer in spring to promote healthy growth and flowering. Deadhead spent flowers to encourage further blooming. Honesty is typically grown as a biennial, meaning it completes its life cycle in two years. In the first year, it focuses on vegetative growth, and in the second year, it flowers and produces seedpods. After the seedpods mature and dry, they can be harvested for decorative purposes. Honesty self-seeds readily, so be prepared for new plants to appear in subsequent years. Pruning is not typically required, but you can trim back the plant after flowering to maintain its shape.

How do I propagate Honesty?

Honesty can be propagated by seeds or by division. To propagate by seeds, collect the seeds from mature seedpods and sow them in spring or fall. Sow seeds directly into the garden or start them indoors in seed trays. Keep the soil moist and provide bright, indirect light. To propagate by division, carefully dig up the plant in spring or fall and divide the root ball into several sections. Replant the divisions in fresh, well-draining soil. Ensure each division has healthy roots and shoots. Division is not always successful, as Honesty can be sensitive to root disturbance. Stem cuttings and keiki propagation are not applicable to Honesty.

Last updated: May 15, 2026 — Plant care data reviewed and verified by our editorial team.