Alyssum vs Purple Fountain Grass 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
Purple Fountain Grass

Purple Fountain Grass

Pennisetum setaceum 'Rubrum'

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
Purple Fountain Grass

Purple Fountain Grass

Pennisetum setaceum 'Rubrum'

Purple Fountain Grass is a striking ornamental grass prized for its arching, burgundy-purple foliage and bottlebrush-like flower plumes. It typically grows in a mounded form, reaching several feet in height and width. While technically a perennial in warmer climates, it is often grown as an annual in cooler regions due to its sensitivity to frost. It is primarily an outdoor plant, grown for its dramatic texture and color in gardens and landscapes. People grow it for its ornamental value, adding movement and visual interest to borders, containers, and mass plantings.

Poaceae Hybrid cultivar; species native to Africa, Southwest Asia
✨ Features: Attractive foliage and flower plumes, drought tolerance, deer resistance
📖 Read Complete Purple Fountain Grass Guide

Quick Plant Comparison

Feature Alyssum Purple Fountain Grass
Light Full sun to partial shade outdoors. Indoors, requires very bright, direct light for at least 6 hours daily. Full sun (at least 6 hours of direct sunlight per day)
Watering Every 2-3 days outdoors in warm weather; every 5-7 days indoors, depending on light and temperature. Every 7-10 days, depending on weather and soil drainage
Humidity 30-50% 20-50%
Temperature 15-24°C 18-30°C
Care Level Expert Expert
Growth Rate Moderate Moderate
Max Height 6-12 inches (indoors, typically smaller) Outdoor: 0.6-1.5 meters. Indoor (unlikely to thrive): 0.3-0.6 meters
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining potting mix. A mix of potting soil, perlite, and vermiculite is suitable. Well-draining soil, such as a sandy loam or a potting mix amended with perlite
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 15 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.

Purple Fountain Grass

Scientific Name Pennisetum setaceum 'Rubrum'
Family Poaceae
Native To Hybrid cultivar; species native to Africa, Southwest Asia
Also Known As Purple Fountain Grass, Red Fountain Grass
Leaves The leaves are long, narrow, and arching, with a deep burgundy-purple color. They have a fine texture and create a graceful, flowing appearance.
Flowers It produces bottlebrush-like flower plumes that are initially a deep burgundy-purple, fading to a tan color as they mature. Flowering typically occurs in summer and fall. It is unlikely to flower indoors.

📏 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.

Purple Fountain Grass

Height Outdoor: 0.6-1.5 meters. Indoor (unlikely to thrive): 0.3-0.6 meters
Spread Outdoor: 0.6-1.2 meters. Indoor (unlikely to thrive): 0.3-0.6 meters
Growth Rate Moderate
Growth Pattern Grows in a mounded, upright form with arching foliage and flower plumes.

🌱 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.

Purple Fountain Grass

Methods: Seed, Division

Difficulty: Moderate

Tips: Divide clumps in spring or early summer. Sow seeds indoors 6-8 weeks before the last frost.

✨ 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

Purple Fountain Grass

Its deep purple foliage and graceful, arching habit make it a standout in any garden. The bottlebrush-like flower plumes add further visual interest and movement.

  • ✓ Adds visual interest and texture to the garden
  • ✓ Attracts birds
  • ✓ Drought tolerant
  • ✓ Deer resistant
  • ✓ Provides movement in the landscape
  • 🐾 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.

Purple Fountain Grass

Repotting Not applicable as it is primarily an outdoor plant. If grown in a container, repot every 1-2 years in spring.
Pruning Cut back dead or damaged foliage as needed. Prune lightly in early spring to encourage new growth.
Fertilizing Balanced slow-release fertilizer in spring; liquid fertilizer diluted to half strength monthly during the growing season
Seasonal Care In colder climates, cut back foliage in late fall after it has turned brown. In warmer climates, prune lightly in early spring to remove dead or damaged growth. Reduce watering in winter.

🌞 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

Purple Fountain Grass

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

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.

Purple Fountain Grass

Water deeply when the top inch of soil feels dry to the touch. Avoid overwatering, which can lead to root rot. Signs of underwatering include drooping or browning leaves. Signs of overwatering include yellowing leaves and soggy soil.

🌡️ Temperature & Humidity

Alyssum

Temperature: 15-24°C

Humidity: 30-50%

Purple Fountain Grass

Temperature: 18-30°C

Humidity: 20-50%

🤔 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.
Purple Fountain Grass

Purple Fountain Grass

Pennisetum setaceum 'Rubrum'
Care: Expert Time: 15 minutes weekly Beginner: No

Gardeners looking for a dramatic ornamental grass to add color and texture to their landscape.

✅ Choose This Plant If...

  • You want a striking focal point in your garden.
  • You need a drought-tolerant plant for a sunny location.
  • You desire a plant with beautiful purple foliage and plumes.
  • You want to attract birds to your garden.
  • You need a deer-resistant plant.

❌ Skip This Plant If...

  • You live in a cold climate and don't want to treat it as an annual.
  • You don't have a sunny location.
  • You are looking for a low-maintenance indoor plant.
📍 Ideal Location: Outdoor garden, sunny border, container on a patio
🎨 Style: Modern, Mediterranean, Southwestern, Cottage
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Pennisetum species are generally considered non-toxic to dogs, cats, and horses.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Purple Fountain Grass ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

🌿

Both plants have similar basic care requirements but differ in appearance and specific needs. Compare plants carefully to find the best fit for your space.

💡 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.

Purple Fountain Grass Care Tips

Purple Fountain Grass is primarily an outdoor plant and will struggle indoors due to its high light requirements. It needs full sun and well-draining soil. While it can be grown in containers, it requires regular watering and fertilization. Overwintering indoors is possible in colder climates, but the plant may not thrive.

  • Plant in well-draining soil in a sunny location.
  • Water deeply but infrequently, allowing the soil to dry out between waterings.
  • Fertilize in spring with a balanced slow-release fertilizer.
  • Cut back foliage in late fall or early spring.
  • Protect from frost in colder climates.
❄️ Winter: In cold climates, cut back foliage after it turns brown. Reduce watering significantly. If overwintering indoors, provide as much light as possible and keep soil slightly moist.
☀️ Summer: Water more frequently during hot, dry weather. Fertilize monthly with a diluted liquid fertilizer to promote growth and flowering.

⚠️ 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.

Purple Fountain Grass

Common Issues: Root rot, Aphids, Spider mites, Leaf spot
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Aphids: Spray with insecticidal soap. Spider mites: Increase humidity and treat with miticide. Leaf spot: Remove affected leaves and apply fungicide.

❓ 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.

Purple Fountain Grass

What are the light requirements for Purple Fountain Grass?

Purple Fountain Grass requires at least 6-8 hours of direct sunlight per day to thrive and develop its characteristic vibrant purple foliage and abundant flower plumes. Insufficient sunlight can lead to leggy growth, faded color, and reduced flowering. When planting, choose a location that receives full sun throughout the day. If growing in containers, rotate the plant regularly to ensure even sun exposure on all sides. In hotter climates, some afternoon shade may be beneficial to prevent scorching, but avoid placing it in deep shade, which will hinder its growth. Supplemental lighting may be necessary if grown indoors during winter months.

How do I care for Purple Fountain Grass?

Purple Fountain Grass thrives in full sun and well-draining soil. Water thoroughly when the top inch of soil feels dry, but avoid overwatering, which can lead to root rot. Fertilize monthly during the growing season (spring and summer) with a balanced fertilizer to promote healthy growth and vibrant blooms. Prune away dead or damaged foliage in late winter or early spring before new growth emerges. In colder climates, treat it as an annual or bring it indoors during the winter. Provide adequate air circulation to prevent fungal diseases. Regularly inspect for pests like aphids or spider mites, and treat accordingly. Avoid planting in overly compacted or poorly draining soil. Mulching around the base can help retain moisture and suppress weeds. Protect from strong winds.

How do I propagate Purple Fountain Grass?

Purple Fountain Grass can be propagated by division. In early spring, carefully dig up the plant and divide the root ball into smaller clumps, ensuring each clump has healthy roots and foliage. Replant the divisions in well-draining soil and water thoroughly. Keep the soil consistently moist until the new plants are established. Division is the most reliable method. Seed propagation is possible but can be inconsistent in producing plants true to the ‘Rubrum’ cultivar. Stem cuttings are not typically used for propagating this grass. Keikis are not applicable as this plant doesn’t produce them. Ensure good air circulation to prevent fungal diseases after dividing.

Last updated: April 30, 2026 — Plant care data reviewed and verified by our editorial team.