Cornflower vs Myrtle Spurge Plant Comparison

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

Cornflower

Cornflower

Centaurea cyanus

VS
Myrtle Spurge

Myrtle Spurge

Euphorbia myrsinites

Cornflower

Cornflower

Centaurea cyanus

Cornflower (Centaurea cyanus) is an annual plant typically grown outdoors for its vibrant blue flowers, though pink, white, and purple varieties exist. It reaches a height of 1 to 3 feet. Its slender, grey-green leaves provide a backdrop for the showy, thistle-like flower heads. While it can be grown indoors, it requires very bright light and is challenging to maintain as a healthy, flowering plant indoors due to its need for full sun and cool temperatures. It is often grown in cottage gardens and wildflower meadows.

Asteraceae Europe, though its exact origin is debated as it has naturalized widely.
✨ Features: Attracts pollinators, edible flowers (though may cause allergic reactions in some individuals), used in herbal teas.
📖 Read Complete Cornflower Guide
Myrtle Spurge

Myrtle Spurge

Euphorbia myrsinites

Myrtle Spurge is a succulent, low-growing perennial characterized by its sprawling habit and blue-gray, spirally arranged leaves. It typically reaches a height of 6-12 inches and spreads up to 24 inches wide. It is primarily grown as an ornamental ground cover in rock gardens or dry landscapes. It produces small, inconspicuous yellowish-green flowers in spring, followed by seed capsules. This plant is naturally an outdoor plant and struggles indoors due to its high light requirements and need for well-draining soil.

Euphorbiaceae Mediterranean region (Southern Europe and North Africa)
✨ Features: Drought tolerance, attractive blue-gray foliage.
📖 Read Complete Myrtle Spurge Guide

Quick Plant Comparison

Feature Cornflower Myrtle Spurge
Light Full sun (at least 6 hours of direct sunlight per day) Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth.
Watering Outdoors: Every 1-2 weeks, depending on rainfall. Indoors: Every 7-10 days, allowing the soil to dry slightly between waterings. Every 2-4 weeks, depending on weather and soil drainage.
Humidity 30-50% 20-40%
Temperature 15-24°C 15-25°C
Care Level Expert Expert
Growth Rate Fast Moderate
Max Height Indoors: 0.3-0.6 meters (1-2 feet). Outdoors: 0.3-0.9 meters (1-3 feet) 6-12 inches (outdoor)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining soil, such as a sandy loam. Prefers slightly alkaline soil. Well-draining, sandy or gravelly soil. Avoid heavy clay soils.
Beginner Friendly With Caution ❌ No
Weekly Maintenance 5-10 minutes weekly (deadheading, watering) 15 minutes monthly (weeding, pruning)

🔬 Botanical Information — Comparing These Plants

Cornflower

Scientific Name Centaurea cyanus
Family Asteraceae
Native To Europe, though its exact origin is debated as it has naturalized widely.
Also Known As Cornflower, Bachelor's Button, Bluebottle, Hurtsickle
Leaves The leaves are slender, lance-shaped, and grey-green in color. They are typically 2-4 inches long and have a slightly hairy texture.
Flowers Cornflowers produce showy, thistle-like flower heads that are typically blue, but can also be pink, white, or purple. They bloom from late spring to early summer. Flowering indoors is rare without supplemental lighting.

Myrtle Spurge

Scientific Name Euphorbia myrsinites
Family Euphorbiaceae
Native To Mediterranean region (Southern Europe and North Africa)
Also Known As Myrtle Spurge, Donkey Spurge, Creeping Spurge, Glaucous Spurge
Leaves Succulent, blue-gray, lance-shaped leaves arranged in a spiral pattern around the stems. Leaves are typically 1-2 inches long.
Flowers Produces small, inconspicuous yellowish-green flowers in spring. Rarely flowers indoors.

📏 Size & Growth — Plant Comparison

Cornflower

Height Indoors: 0.3-0.6 meters (1-2 feet). Outdoors: 0.3-0.9 meters (1-3 feet)
Spread Indoors: 0.2-0.3 meters (0.6-1 foot). Outdoors: 0.2-0.45 meters (0.6-1.5 feet)
Growth Rate Fast
Growth Pattern Cornflowers have an upright growth habit, typically reaching 1 to 3 feet tall. They are annuals, meaning they complete their life cycle in one growing season.

Myrtle Spurge

Height 6-12 inches (outdoor)
Spread Up to 24 inches (outdoor)
Growth Rate Moderate
Growth Pattern Sprawling, low-growing perennial that forms a dense mat.

🌱 Propagation — Comparing Plant Growth

Cornflower

Methods: Seed

Difficulty: Easy

Tips: Sow seeds directly into the garden in early spring or fall. Indoors, start seeds 6-8 weeks before the last frost. Provide light and consistent moisture for germination.

Myrtle Spurge

Methods: Seed, Stem cuttings

Difficulty: Moderate

Tips: Take stem cuttings in spring or summer, allow the cut end to callous over for a few days, and then plant in well-draining soil. Wear gloves to avoid skin irritation from the sap.

✨ Benefits & Features — Comparing Plant Value

Cornflower

The intense blue color of the flowers is relatively rare in the plant kingdom. They are also known for attracting beneficial insects to the garden. The flowers are edible and have a slightly sweet, clove-like flavor.

  • ✓ Attracts pollinators like bees and butterflies.
  • ✓ Adds vibrant color to the garden.
  • ✓ Edible flowers can be used in salads and teas (with caution).
  • ✓ Relatively low-maintenance once established.
  • ✓ Can be used as a cut flower.
  • ⚠️ Toxic to pets

Myrtle Spurge

The spirally arranged, blue-gray leaves give it a distinctive appearance. The milky sap is toxic and can cause skin irritation.

  • ✓ Drought tolerance reduces water usage.
  • ✓ Provides visual interest with its unique foliage.
  • ✓ Low maintenance once established.
  • ✓ Attracts pollinators.
  • ✓ Controls erosion on slopes.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Cornflower

Repotting Not applicable as it's typically grown as an annual. If grown indoors, repot only if rootbound, using a slightly larger pot.
Pruning Deadhead spent flowers regularly to encourage continued blooming. Pinch back stems to promote bushier growth.
Fertilizing A balanced liquid fertilizer (10-10-10) diluted to half strength, applied monthly during the growing season.
Seasonal Care Spring: Sow seeds. Summer: Deadhead spent flowers to encourage more blooms. Fall: Collect seeds for next year. Winter: Annual, so plant dies back.

Myrtle Spurge

Repotting Not applicable as it's not suitable for indoor growing.
Pruning Prune after flowering to maintain shape and prevent excessive seed production. Remove any dead or damaged stems.
Fertilizing Apply a balanced, slow-release fertilizer in early spring at half strength.
Seasonal Care In winter, reduce watering and protect from excessive moisture. In spring and summer, water more frequently and fertilize lightly.

🌞 Light Requirements

Cornflower

Full sun (at least 6 hours of direct sunlight per day)

Low light tolerant: ❌ No

Myrtle Spurge

Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth.

Low light tolerant: ❌ No

💧 Watering Needs

Cornflower

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Indoors, ensure good drainage. Outdoors, established plants are somewhat drought-tolerant.

Myrtle Spurge

Water deeply but infrequently, allowing the soil to dry out completely between waterings. Overwatering can lead to root rot. Signs of underwatering include shriveled leaves. Signs of overwatering include yellowing leaves and a mushy stem.

🌡️ Temperature & Humidity

Cornflower

Temperature: 15-24°C

Humidity: 30-50%

Myrtle Spurge

Temperature: 15-25°C

Humidity: 20-40%

🤔 Which Plant Is Right For You?

Cornflower

Cornflower

Centaurea cyanus
Care: Expert Time: 5-10 minutes weekly (deadheading, watering) Beginner: With-caution

Gardeners who want a low-maintenance, colorful addition to their flower beds or wildflower meadows.

✅ Choose This Plant If...

  • You want a vibrant blue flower in your garden.
  • You want to attract pollinators to your yard.
  • You want an easy-to-grow annual flower.
  • You want to add edible flowers to salads (with caution due to potential allergic reactions).
  • You want to create a cottage garden or wildflower meadow.

❌ Skip This Plant If...

  • You don't have a sunny location.
  • You have pets that might ingest the plant.
  • You want a low-maintenance indoor plant.
📍 Ideal Location: Outdoors: Sunny garden bed or wildflower meadow. Indoors: South-facing window with supplemental lighting.
🎨 Style: Cottagecore, Bohemian, Traditional, Wildflower
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Centaurea species contain sesquiterpene lactones which can cause gastrointestinal upset if ingested by dogs, cats, or horses. Symptoms include vomiting, diarrhea, and anorexia. All parts of the plant are considered toxic.
Myrtle Spurge

Myrtle Spurge

Euphorbia myrsinites
Care: Expert Time: 15 minutes monthly (weeding, pruning) Beginner: No

Experienced gardeners looking for a drought-tolerant ground cover in sunny, well-drained locations.

✅ Choose This Plant If...

  • You need a drought-tolerant ground cover for a sunny area.
  • You appreciate the unique blue-gray foliage.
  • You are an experienced gardener familiar with handling toxic plants.
  • You want a low-maintenance plant once established.
  • You have a rock garden or xeriscape landscape.

❌ Skip This Plant If...

  • You have pets or small children who may ingest the plant.
  • You are a beginner gardener.
  • You do not have a sunny outdoor space.
  • You are sensitive to latex or have skin allergies.
📍 Ideal Location: Outdoor rock garden or sunny, well-drained slope.
🎨 Style: Mediterranean, Xeriscape, Rock Garden
🏠 Apartment Friendly: No
⚠️ All parts of the plant are toxic, containing a milky sap that can cause skin irritation and gastrointestinal upset if ingested. According to the ASPCA, Euphorbia species are toxic to dogs, cats, and horses. Symptoms include drooling, vomiting, diarrhea, and skin irritation.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

📈

Cornflower has fast growth, while Myrtle Spurge grows moderate.

💡 Pro Tips For Comparing These Plants

Cornflower Care Tips

Cornflowers are easy to grow outdoors in full sun and well-draining soil. Indoor cultivation is challenging due to the plant's high light requirements and need for cool temperatures. Supplemental lighting is almost essential for indoor flowering.

  • Provide full sun for optimal flowering.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Avoid overwatering to prevent root rot.
  • If growing indoors, supplement with grow lights.
  • Sow seeds directly in the garden for best results.
❄️ Winter: Cornflowers are annuals, so they will die back in the winter. Collect seeds for planting the following spring.
☀️ Summer: Deadhead spent flowers regularly to encourage continued blooming. Water during dry spells. Provide support if the plants become leggy.

Myrtle Spurge Care Tips

Myrtle Spurge is an outdoor plant that requires full sun and well-draining soil. It is not suitable for indoor growing due to its high light requirements and potential for toxicity. It is drought-tolerant and relatively low-maintenance once established, but requires careful handling due to its toxic sap.

  • Always wear gloves and eye protection when handling Myrtle Spurge.
  • Remove seed heads to prevent unwanted spread.
  • Ensure excellent drainage to prevent root rot.
  • Water deeply but infrequently.
  • Provide full sun for optimal growth and color.
❄️ Winter: Reduce watering significantly during winter. Protect from excessive moisture and frost in colder climates.
☀️ Summer: Water more frequently during hot, dry periods. Provide some afternoon shade in extremely hot climates.

⚠️ Common Problems & Solutions — Plant Care Comparison

Cornflower

Common Issues: Powdery mildew, aphids, root rot, leggy growth (indoors)
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Aphids: Spray with insecticidal soap. Root rot: Ensure well-draining soil and avoid overwatering. Leggy growth: Provide more light and pinch back stems.

Myrtle Spurge

Common Issues: Root rot, Aphids, Skin irritation from sap, Invasive spread
Solutions: Ensure well-draining soil and avoid overwatering. Treat aphids with insecticidal soap. Wear gloves and protective eyewear when handling the plant. Remove seed heads to prevent unwanted spread.

❓ Frequently Asked Questions — Comparing These Plants

Cornflower

What are the light requirements for Cornflower?

Cornflowers require at least six hours of direct sunlight per day to thrive and produce abundant blooms. When grown indoors, place them near a south-facing window where they can receive ample sunlight. If natural light is insufficient, supplement with grow lights. Insufficient light can lead to leggy growth and reduced flowering. Rotate the plant regularly to ensure even light exposure on all sides. Avoid placing cornflowers in areas with heavy shade, as this will hinder their growth and flowering potential. Strong, direct morning sunlight is ideal, followed by slightly filtered light in the afternoon.

How do I care for Cornflower?

Cornflowers thrive in full sun and well-drained soil. Water regularly, especially during dry periods, but avoid overwatering to prevent root rot. Fertilize monthly with a balanced fertilizer during the growing season to promote abundant blooms. Deadhead spent flowers to encourage continuous blooming. Cornflowers are relatively low-maintenance and can tolerate a range of conditions, but they prefer cooler temperatures. Protect them from strong winds, which can damage their delicate stems. In warmer climates, provide some afternoon shade to prevent scorching. Monitor for pests like aphids and treat promptly if necessary. With proper care, cornflowers will reward you with a long season of beautiful blooms.

How do I propagate Cornflower?

Cornflowers are primarily propagated by seed. Direct sow seeds in the garden in early spring or fall. Sow seeds thinly and cover lightly with soil. Keep the soil moist until germination. Alternatively, start seeds indoors and transplant seedlings outdoors after the last frost. Cornflowers can also self-sow if allowed to go to seed. While division and cuttings are possible, they are less common methods for cornflowers. Collect seeds from dried flower heads for future planting. Ensure seeds are stored in a cool, dry place.

Myrtle Spurge

What are the light requirements for Myrtle Spurge?

Myrtle Spurge thrives in bright, direct sunlight. Aim for at least 6 hours of sunlight per day. An east- or south-facing window is ideal. If grown outdoors, choose a location that receives full sun. Insufficient light can lead to etiolation, where the plant stretches towards the light source, resulting in weak, leggy growth. Rotate the plant regularly to ensure even light exposure on all sides. In regions with intense summer sun, provide some afternoon shade to prevent scorching. Supplement with grow lights if natural light is limited, particularly during winter months.

How do I care for Myrtle Spurge?

Myrtle Spurge requires well-draining soil, such as a cactus or succulent mix, to prevent root rot. Water thoroughly when the soil is completely dry, typically every 2-4 weeks, depending on environmental conditions. Provide bright, direct sunlight for at least 6 hours a day; however, protect it from intense afternoon sun in hot climates. Fertilize sparingly, only during the growing season (spring and summer), using a balanced, diluted succulent fertilizer. Prune dead or damaged leaves to maintain its appearance. Be extremely cautious of the milky sap, which can cause skin irritation. Wear gloves when handling. Avoid overwatering, especially during winter dormancy.

How do I propagate Myrtle Spurge?

Myrtle Spurge can be propagated through stem cuttings, leaf cuttings, or offsets. For stem cuttings, allow the cut end to callous over for a few days before planting in well-draining soil. Rooting hormone can aid in the process. Leaf cuttings can be placed on top of well-draining soil and misted occasionally. Offsets, or small plantlets that grow around the base of the mother plant, can be carefully separated and potted individually. Wear gloves when handling cuttings to avoid skin irritation from the sap. Provide bright, indirect light and maintain consistent moisture until roots develop. Propagation is best done during the growing season (spring or summer).

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