Alyssum vs Bells of Ireland Plant Comparison

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

Alyssum

Alyssum

Lobularia maritima

VS
Bells of Ireland

Bells of Ireland

Moluccella laevis

Alyssum

Alyssum

Lobularia maritima

Sweet Alyssum (Lobularia maritima) is a low-growing, spreading annual or short-lived perennial, typically grown as an annual. It reaches a height of 6-12 inches and spreads 12-18 inches wide. It features masses of tiny, fragrant flowers, usually white but also available in pink, purple, and yellow shades. Primarily an outdoor plant, it's popular for borders, rock gardens, and containers due to its profuse blooms and sweet honey-like scent. While it can be attempted indoors, maintaining sufficient light and cool temperatures is challenging.

Brassicaceae Mediterranean region, Canary Islands
✨ Features: Fragrant flowers, attracts pollinators
📖 Read Complete Alyssum Guide
Bells of Ireland

Bells of Ireland

Moluccella laevis

Bells of Ireland is an annual flowering plant known for its tall spikes of vibrant green, bell-shaped calyces (modified leaves) that surround tiny, inconspicuous white flowers. It typically grows to a height of 2-3 feet. While it can be grown indoors, it's primarily an outdoor plant, often cultivated in gardens for its unique architectural form and long-lasting cut flowers. People grow it for its ornamental value, particularly in floral arrangements, where its bright green color adds a striking contrast.

Lamiaceae (Mint family) Western Asia (Turkey, Syria, Caucasus)
✨ Features: Unique architectural form, excellent cut flower, attracts pollinators.
📖 Read Complete Bells of Ireland Guide

Quick Plant Comparison

Feature Alyssum Bells of Ireland
Light Full sun to partial shade outdoors. Indoors, requires very bright, direct light for at least 6 hours daily. Full sun to partial shade outdoors. Indoors, requires very bright, direct light for at least 6 hours daily.
Watering Every 2-3 days outdoors in warm weather; every 5-7 days indoors, depending on light and temperature. Outdoors: 2-3 times per week, depending on weather. Indoors: Every 5-7 days, depending on light and humidity.
Humidity 30-50% 40-60%
Temperature 15-24°C 15-24°C
Care Level Expert Expert
Growth Rate Moderate Fast
Max Height 6-12 inches (indoors, typically smaller) Indoors: 0.6-1 meter (2-3 feet). Outdoors: 0.6-1 meter (2-3 feet)
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining potting mix. A mix of potting soil, perlite, and vermiculite is suitable. Well-draining potting mix or garden soil. A mix of potting soil, perlite, and vermiculite is suitable.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 30 minutes weekly

🔬 Botanical Information — Comparing These Plants

Alyssum

Scientific Name Lobularia maritima
Family Brassicaceae
Native To Mediterranean region, Canary Islands
Also Known As Sweet Alyssum, Sweet Alison
Leaves Small, lance-shaped, and grayish-green. The leaves are typically less than an inch long and have a slightly hairy texture.
Flowers Flowers profusely outdoors. Indoors, flowering is possible with sufficient light. The flowers are tiny, four-petaled, and typically white, but also available in pink, purple, and yellow shades. They are clustered together in masses, creating a showy display.

Bells of Ireland

Scientific Name Moluccella laevis
Family Lamiaceae (Mint family)
Native To Western Asia (Turkey, Syria, Caucasus)
Also Known As Bells of Ireland, Molucca Balm, Shellflower
Leaves The leaves are light green, oval to rounded in shape, and have slightly toothed edges. They are arranged oppositely along the stem and are generally inconspicuous compared to the prominent calyces.
Flowers The actual flowers are small, white, and relatively insignificant, hidden within the larger green calyces. Flowering typically occurs in summer.

📏 Size & Growth — Plant Comparison

Alyssum

Height 6-12 inches (indoors, typically smaller)
Spread 12-18 inches (indoors, less spreading)
Growth Rate Moderate
Growth Pattern Low-growing, spreading, and mounding. It forms a dense mat of foliage and flowers.

Bells of Ireland

Height Indoors: 0.6-1 meter (2-3 feet). Outdoors: 0.6-1 meter (2-3 feet)
Spread Indoors: 30-45 cm (12-18 inches). Outdoors: 30-45 cm (12-18 inches)
Growth Rate Fast
Growth Pattern Upright, branching plant with tall spikes of bell-shaped calyces. It grows quickly during the growing season and typically dies back after flowering.

🌱 Propagation — Comparing Plant Growth

Alyssum

Methods: Seed, Stem cuttings

Difficulty: Easy

Tips: For seeds, sow indoors 6-8 weeks before the last frost or directly outdoors after the last frost. For stem cuttings, take 2-3 inch cuttings and root them in water or moist potting mix.

Bells of Ireland

Methods: Seed

Difficulty: Moderate

Tips: Sow seeds indoors 6-8 weeks before the last frost or directly outdoors after the last frost. Seeds require light to germinate, so press them gently into the soil surface. Keep the soil consistently moist.

✨ Benefits & Features — Comparing Plant Value

Alyssum

Sweet Alyssum is known for its profuse blooms and sweet, honey-like fragrance. Its low-growing, spreading habit makes it ideal for borders and rock gardens. It is also attractive to beneficial insects.

  • ✓ Attracts pollinators to the garden.
  • ✓ Provides a sweet, honey-like fragrance.
  • ✓ Adds a splash of color to borders and containers.
  • ✓ Can be used as a ground cover.
  • ✓ Provides a calming aesthetic.
  • ⚠️ Toxic to pets

Bells of Ireland

The most striking feature is the bright green, bell-shaped calyces that surround the tiny white flowers. These calyces persist long after the flowers have faded, providing extended ornamental value. It is not native to Ireland, despite its common name.

  • ✓ Adds unique architectural interest to gardens and floral arrangements.
  • ✓ Provides a vibrant green color that contrasts well with other flowers.
  • ✓ Attracts pollinators like bees and butterflies.
  • ✓ Symbolizes luck and good fortune.
  • ✓ Can be dried and used in dried flower arrangements.
  • 🐾 Pet Safe

📅 Maintenance Schedule — Plant Care Comparison

Alyssum

Repotting Not typically needed for annuals. If grown as a perennial, repot in spring every 1-2 years.
Pruning Pinch back stems regularly to encourage bushier growth and more blooms. Deadhead spent flowers.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-4 weeks during the growing season.
Seasonal Care In summer, provide afternoon shade in hot climates. In winter, reduce watering and protect from frost. Deadhead spent flowers to encourage continuous blooming.

Bells of Ireland

Repotting Not typically repotted as it is an annual. If grown indoors, repotting may be necessary if the plant becomes root-bound.
Pruning Pinch back young plants to encourage bushier growth. Remove spent flower spikes to promote continued 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 Spring/Summer: Active growth, regular watering and fertilization. Fall: Seed collection. Winter: Minimal watering, may die back in colder climates (annual).

🌞 Light Requirements

Alyssum

Full sun to partial shade outdoors. Indoors, requires very bright, direct light for at least 6 hours daily.

Low light tolerant: ❌ No

Bells of Ireland

Full sun to partial shade outdoors. Indoors, requires very bright, direct light for at least 6 hours daily.

Low light tolerant: ❌ No

💧 Watering Needs

Alyssum

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Allow the soil to drain completely after watering. Indoors, monitor closely as soil dries out faster in bright light.

Bells of Ireland

Outdoors: Water regularly, keeping the soil consistently moist but not waterlogged. Indoors: Water thoroughly when the top inch of soil feels dry. Overwatering can lead to root rot; underwatering will cause wilting and browning of the calyces.

🌡️ Temperature & Humidity

Alyssum

Temperature: 15-24°C

Humidity: 30-50%

Bells of Ireland

Temperature: 15-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Alyssum

Alyssum

Lobularia maritima
Care: Expert Time: 15 minutes weekly Beginner: No

Experienced gardeners who want a fragrant, flowering plant for outdoor borders, rock gardens, or containers.

✅ Choose This Plant If...

  • You want a plant with a sweet, honey-like fragrance.
  • You need a low-growing plant for borders or rock gardens.
  • You want to attract pollinators to your garden.
  • You enjoy plants that bloom profusely.
  • You are an experienced gardener willing to provide the high light levels needed indoors.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You cannot provide very bright, direct light.
  • You prefer low-maintenance indoor plants.
📍 Ideal Location: Outdoors: Sunny borders, rock gardens, containers. Indoors: South-facing windowsill with direct sunlight.
🎨 Style: Cottage, Traditional, Romantic
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Sweet Alyssum is toxic to dogs, cats, and horses. Symptoms include vomiting and diarrhea. All parts of the plant are considered toxic.
Bells of Ireland

Bells of Ireland

Moluccella laevis
Care: Expert Time: 30 minutes weekly Beginner: No

Experienced gardeners who want a unique and striking addition to their cut flower arrangements.

✅ Choose This Plant If...

  • You want a unique and striking addition to your garden or floral arrangements.
  • You enjoy the challenge of growing plants that require specific conditions.
  • You are looking for a plant with a strong architectural presence.
  • You want to attract pollinators to your garden.
  • You need a long-lasting cut flower with a vibrant green color.

❌ Skip This Plant If...

  • You have limited sunlight indoors and cannot provide supplemental lighting.
  • You are a beginner gardener looking for an easy-to-grow plant.
  • You live in a very hot or humid climate, which can increase the risk of fungal diseases.
📍 Ideal Location: Outdoors: Sunny garden bed or border. Indoors: South-facing window with supplemental grow lights.
🎨 Style: Cottagecore, Eclectic, Traditional, Bohemian
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Moluccella laevis is not listed as toxic to dogs, cats, or horses.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Bells of Ireland ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

📈

Alyssum has moderate growth, while Bells of Ireland grows fast.

💡 Pro Tips For Comparing These Plants

Alyssum Care Tips

Sweet Alyssum is primarily an outdoor plant. Indoor cultivation is challenging due to its high light requirements and preference for cooler temperatures. It needs very bright, direct light and well-draining soil. Overwatering and lack of sufficient light are common problems indoors.

  • Provide at least 6 hours of direct sunlight daily for indoor plants.
  • Use well-draining soil to prevent root rot.
  • Deadhead spent flowers regularly to encourage continuous blooming.
  • Fertilize every 2-4 weeks during the growing season.
  • Monitor for pests like aphids and treat promptly.
❄️ Winter: Reduce watering in winter. Protect from frost if grown as a perennial. Provide as much light as possible indoors.
☀️ Summer: Provide afternoon shade in hot climates. Water more frequently during hot, dry weather. Deadhead spent flowers regularly.

Bells of Ireland Care Tips

Bells of Ireland are best suited for outdoor gardens. Growing them indoors is challenging due to their high light requirements. Supplemental lighting is almost always necessary. Consistent watering and well-draining soil are crucial to prevent root rot. Requires careful monitoring for pests and diseases.

  • Start seeds indoors 6-8 weeks before the last frost for earlier blooms.
  • Provide well-draining soil to prevent root rot.
  • Water regularly, especially during hot and dry weather.
  • Fertilize every 2-4 weeks during the growing season with a balanced liquid fertilizer.
  • Pinch back young plants to encourage bushier growth.
❄️ Winter: As an annual, Bells of Ireland typically dies back in the winter. Collect seeds for planting the following spring.
☀️ Summer: Provide consistent moisture and protection from extreme heat. Fertilize regularly to promote continued blooming. Monitor for pests and diseases.

⚠️ Common Problems & Solutions — Plant Care Comparison

Alyssum

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

Bells of Ireland

Common Issues: Powdery mildew, root rot, aphids, spider mites
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Root rot: Ensure well-draining soil and avoid overwatering. Aphids/Spider mites: Insecticidal soap or neem oil.

❓ Frequently Asked Questions — Comparing These Plants

Alyssum

What are the light requirements for Alyssum?

Alyssum prefers full sun, requiring at least 6 hours of direct sunlight each day to thrive and produce abundant blooms. However, in hotter climates, it benefits from some afternoon shade to prevent scorching of the delicate flowers and foliage. Insufficient light can lead to leggy growth, reduced flowering, and pale foliage.

How do I care for Alyssum?

Alyssum thrives in full sun to partial shade. Aim for at least 6 hours of sunlight daily for optimal blooming. Plant in well-draining soil with a slightly acidic to neutral pH (6.0-7.0). Water regularly, allowing the soil to dry slightly between waterings. Avoid overwatering, as this can lead to root rot. Fertilize every 2-3 weeks during the growing season with a balanced liquid fertilizer, focusing on formulas that promote blooming.

How do I propagate Alyssum?

Alyssum can be propagated through seeds, stem cuttings, and division. 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 keep them in a humid environment until rooted.

Bells of Ireland

What are the light requirements for Bells of Ireland?

Bells of Ireland crave sunlight. They need at least 6-8 hours of direct sunlight each day to produce vibrant green calyces and strong stems. Insufficient light can lead to leggy growth, pale coloring, and reduced blooming. When grown indoors, place them near a south-facing window where they can receive ample sunlight. If natural light is limited, supplement with grow lights. Rotate the plants regularly to ensure even light exposure on all sides. When starting seeds indoors, use grow lights to ensure healthy seedling development.

How do I care for Bells of Ireland?

Bells of Ireland require full sun, at least 6-8 hours daily, to thrive. Plant them in well-draining soil with a slightly acidic to neutral pH (6.0-7.0). Water regularly, keeping the soil consistently moist but not waterlogged, especially during hot weather. Fertilize every 2-3 weeks with a balanced liquid fertilizer during the growing season (spring and summer).

How do I propagate Bells of Ireland?

Bells of Ireland are typically propagated by seed.

Last updated: May 3, 2026 — Plant care data reviewed and verified by our editorial team.