Ornamental Grass vs Peruvian Lily Plant Comparison

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

Ornamental Grass

Ornamental Grass

Pennisetum setaceum

VS
Peruvian Lily

Peruvian Lily

Alstroemeria spp.

Ornamental Grass

Ornamental Grass

Pennisetum setaceum

Pennisetum setaceum, commonly known as Fountain Grass, is a perennial grass prized for its graceful, arching foliage and bottlebrush-like flower plumes. Typically grown as an annual in cooler climates, it forms dense clumps of slender, linear leaves. The flower plumes, which appear in late summer and fall, add significant ornamental value. While primarily an outdoor plant, it is sometimes grown indoors, though it requires very bright light to thrive. Fountain grass is popular for its texture, movement in the wind, and overall aesthetic appeal in gardens and landscapes.

Poaceae Tropical Africa, Southwest Asia, Arabian Peninsula
✨ Features: Ornamental plumes, adds texture and movement to landscapes
📖 Read Complete Ornamental Grass Guide
Peruvian Lily

Peruvian Lily

Alstroemeria spp.

Alstroemeria, commonly known as Peruvian Lily, is a genus of flowering plants characterized by its vibrant, trumpet-shaped flowers and lance-shaped leaves. These rhizomatous perennials are primarily grown outdoors in gardens and borders, valued for their long-lasting blooms in a variety of colors, including pink, red, orange, yellow, and white. While they can be grown indoors, they require very bright light and may not flower as prolifically as they do outdoors. Their rhizomatous nature means they can spread quickly.

Alstroemeriaceae South America, primarily Chile and Brazil
✨ Features: Long-lasting cut flowers, wide range of colors
📖 Read Complete Peruvian Lily Guide

Quick Plant Comparison

Feature Ornamental Grass Peruvian Lily
Light Full sun (at least 6 hours of direct sunlight daily) Full sun to partial shade. Requires at least 6 hours of direct sunlight for optimal blooming.
Watering Every 1-2 weeks, depending on environmental conditions and pot size Every 5-7 days during the growing season, less frequently in winter.
Humidity 30-50% 40-60%
Temperature 18-27°C 15-24°C
Care Level Expert Expert
Growth Rate Moderate Moderate To Fast, Aggressive Spreader Via Rhizomes
Max Height 0.6-1.2 meters (indoors, typically smaller) 30-90 cm (indoors, typically smaller)
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil Well-draining soil; a mix of potting soil, sand, and perlite is suitable Well-draining, slightly acidic soil mix. A mix of potting soil, perlite, and peat moss is suitable.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 15 minutes weekly

🔬 Botanical Information — Comparing These Plants

Ornamental Grass

Scientific Name Pennisetum setaceum
Family Poaceae
Native To Tropical Africa, Southwest Asia, Arabian Peninsula
Also Known As Fountain Grass, Crimson Fountain Grass, Purple Fountain Grass
Leaves The leaves are slender, linear, and typically green or purple, depending on the cultivar. They have a slightly rough texture and arch gracefully from the base of the plant.
Flowers While it can flower indoors under ideal conditions, it is less common than when grown outdoors. The flowers are bottlebrush-like plumes, typically pink, purple, or white, and appear in late summer and fall.

Peruvian Lily

Scientific Name Alstroemeria spp.
Family Alstroemeriaceae
Native To South America, primarily Chile and Brazil
Also Known As Peruvian Lily, Lily of the Incas, Parrot Lily, Princess Lily
Leaves Lance-shaped, green leaves that twist upside down (resupinate). They are typically 5-10 cm long and arranged alternately along the stems.
Flowers Flowers are trumpet-shaped and come in a wide range of colors, including pink, red, orange, yellow, and white. They often have speckled or striped patterns. While they can flower indoors with sufficient light, blooming is typically less prolific than outdoors.

📏 Size & Growth — Plant Comparison

Ornamental Grass

Height 0.6-1.2 meters (indoors, typically smaller)
Spread 0.6-0.9 meters
Growth Rate Moderate
Growth Pattern Forms dense, upright clumps of arching foliage. The flower plumes extend above the foliage, creating a fountain-like appearance.

Peruvian Lily

Height 30-90 cm (indoors, typically smaller)
Spread 30-60 cm (spreads via rhizomes)
Growth Rate Moderate To Fast, Aggressive Spreader Via Rhizomes
Growth Pattern Upright, clumping perennial that spreads via rhizomes. Can become quite dense over time.

🌱 Propagation — Comparing Plant Growth

Ornamental Grass

Methods: Seed, Division

Difficulty: Easy

Tips: For seed propagation, sow seeds indoors in early spring. For division, separate clumps in spring or fall, ensuring each division has healthy roots and shoots.

Peruvian Lily

Methods: Division, Seed

Difficulty: Moderate

Tips: Divide rhizomes in early spring or fall. Sow seeds in spring after a period of cold stratification.

✨ Benefits & Features — Comparing Plant Value

Ornamental Grass

Its graceful, arching foliage and bottlebrush-like flower plumes make it a visually striking plant. The movement of the foliage in the wind adds a dynamic element to landscapes and indoor spaces. While often grown as an annual, it can be overwintered indoors with proper care.

  • ✓ Adds visual interest and texture to indoor spaces
  • ✓ Can create a calming and relaxing atmosphere
  • ✓ Provides a touch of the outdoors indoors
  • ✓ Offers a unique aesthetic compared to typical houseplants
  • ✓ Can be used as a focal point in a room
  • 🐾 Pet Safe

Peruvian Lily

Alstroemeria flowers exhibit resupination, where the leaves twist upside down. They also have a long vase life, making them popular cut flowers.

  • ✓ Provides vibrant colors to the garden.
  • ✓ Attracts pollinators like bees and butterflies.
  • ✓ Long-lasting cut flowers for indoor enjoyment.
  • ✓ Can be used in floral arrangements.
  • ✓ Offers a sense of accomplishment for experienced gardeners.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Ornamental Grass

Repotting Repot annually in spring if grown in a container, or when the plant becomes root-bound.
Pruning Cut back dead or damaged foliage as needed. In late winter or early spring, cut back the entire plant to a few inches above the ground to encourage new growth.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, applied monthly during the growing season (spring and summer)
Seasonal Care In winter, reduce watering and withhold fertilizer. If grown as an annual, it will die back with frost. In summer, ensure adequate watering and sun exposure.

Peruvian Lily

Repotting Every 1-2 years, or as needed when the plant becomes root-bound. Divide rhizomes during repotting to control spread.
Pruning Deadhead spent flowers regularly. Cut back foliage in late fall after it has died back.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-4 weeks during the growing season.
Seasonal Care In winter, reduce watering and protect from frost. In summer, provide adequate water and sunlight. Deadhead spent flowers to encourage further blooming.

🌞 Light Requirements

Ornamental Grass

Full sun (at least 6 hours of direct sunlight daily)

Low light tolerant: ❌ No

Peruvian Lily

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

Low light tolerant: ❌ No

💧 Watering Needs

Ornamental Grass

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. In containers, ensure proper drainage. Signs of underwatering include drooping or browning leaves; overwatering can cause yellowing leaves and a soggy soil.

Peruvian Lily

Water thoroughly when the top inch of soil feels dry to the touch. Avoid overwatering, which can lead to root rot. Reduce watering during the dormant period. Signs of overwatering include yellowing leaves and soggy soil. Underwatering is indicated by wilting and dry, crispy leaves.

🌡️ Temperature & Humidity

Ornamental Grass

Temperature: 18-27°C

Humidity: 30-50%

Peruvian Lily

Temperature: 15-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Ornamental Grass

Ornamental Grass

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

Experienced gardeners who can provide the necessary sunlight and care for this outdoor plant indoors.

✅ Choose This Plant If...

  • You want a visually striking plant with graceful, arching foliage.
  • You appreciate the texture and movement that ornamental grasses bring to a space.
  • You have a very sunny indoor location or are willing to use grow lights.
  • You enjoy the bottlebrush-like flower plumes that appear in late summer and fall.
  • You are an experienced gardener who enjoys a challenge.

❌ Skip This Plant If...

  • You have limited sunlight indoors.
  • You are a beginner gardener.
  • You prefer low-maintenance plants.
📍 Ideal Location: South-facing window or sunroom with ample sunlight
🎨 Style: Bohemian, Modern, Naturalistic
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Pennisetum species are generally considered non-toxic to dogs, cats, and horses.
Peruvian Lily

Peruvian Lily

Alstroemeria spp.
Care: Expert Time: 15 minutes weekly Beginner: No

Experienced gardeners who want vibrant, long-lasting blooms in their outdoor gardens.

✅ Choose This Plant If...

  • You want long-lasting cut flowers.
  • You desire a vibrant array of colors in your garden.
  • You have a sunny outdoor space.
  • You enjoy plants that attract pollinators.
  • You are an experienced gardener looking for a rewarding challenge.

❌ Skip This Plant If...

  • You have pets that may ingest the plant.
  • You lack a very bright, sunny location for indoor growing.
  • You are a beginner gardener seeking an easy-care plant.
📍 Ideal Location: Outdoor garden or sunny patio. Indoors, a south-facing window is best, but may still not be sufficient for abundant blooms.
🎨 Style: Cottage, Traditional, Bohemian
🏠 Apartment Friendly: Limited
⚠️ Toxic to cats, dogs, and horses. All parts of the plant are toxic, especially the tubers. Symptoms include vomiting, diarrhea, and skin irritation.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

📈

Ornamental Grass has moderate growth, while Peruvian Lily grows moderate to fast, aggressive spreader via rhizomes.

💡 Pro Tips For Comparing These Plants

Ornamental Grass Care Tips

Fountain Grass is primarily an outdoor plant and requires full sun to thrive. Growing it indoors is challenging due to its high light requirements. It needs well-draining soil, regular watering, and occasional fertilization. Indoor plants will likely be smaller and less vigorous than those grown outdoors.

  • Provide at least 6 hours of direct sunlight daily, supplementing with grow lights if necessary.
  • Use a well-draining potting mix to prevent root rot.
  • Water thoroughly when the top inch of soil feels dry, but avoid overwatering.
  • Fertilize monthly during the growing season with a balanced liquid fertilizer.
  • Prune back dead or damaged foliage regularly to maintain its appearance.
❄️ Winter: Reduce watering significantly during the winter months. Withhold fertilizer and provide as much light as possible. Maintain temperatures above 10°C.
☀️ Summer: Ensure adequate watering during the summer months, especially during hot and dry periods. Provide ample sunlight and fertilize monthly to promote healthy growth.

Peruvian Lily Care Tips

Peruvian Lilies are best suited for outdoor gardens due to their high light requirements and spreading habit. Indoor cultivation is challenging, requiring very bright light and careful watering. They are toxic to pets. Expect less prolific flowering indoors.

  • Provide well-draining soil to prevent root rot.
  • Water deeply but infrequently, allowing the soil to dry slightly between waterings.
  • Fertilize regularly during the growing season with a balanced fertilizer.
  • Deadhead spent flowers to encourage more blooms.
  • Protect from frost in colder climates.
❄️ Winter: Reduce watering during the dormant period. Protect from frost in colder climates by mulching or moving potted plants indoors.
☀️ Summer: Provide adequate water and sunlight. Deadhead spent flowers regularly to encourage further blooming. Monitor for pests and diseases.

⚠️ Common Problems & Solutions — Plant Care Comparison

Ornamental Grass

Common Issues: Insufficient light, Root rot, Pest infestations (aphids, spider mites)
Solutions: Provide more light by moving the plant to a sunnier location or using a grow light.|Ensure proper drainage and avoid overwatering.|Treat infestations with insecticidal soap or neem oil.

Peruvian Lily

Common Issues: Root rot, Aphids, Spider mites, Lack of flowering (indoors)
Solutions: Ensure well-draining soil and avoid overwatering. Treat aphids and spider mites with insecticidal soap. Provide adequate light to encourage flowering.

❓ Frequently Asked Questions — Comparing These Plants

Ornamental Grass

What are the light requirements for Ornamental Grass?

Ornamental grasses require ample sunlight to thrive and produce their characteristic flower plumes. Aim for at least six hours of direct sunlight per day. A south-facing window is ideal for indoor plants. Insufficient light can result in leggy growth, poor flowering, and faded foliage color. If your grass is not receiving enough natural light, consider supplementing with a grow light. Rotate the plant regularly to ensure even light exposure on all sides. Some varieties can tolerate partial shade, but full sun is generally preferred for optimal performance. Observe your plant closely and adjust its location as needed to provide the best possible light conditions.

How do I care for Ornamental Grass?

Ornamental grasses thrive with regular care. Provide them with at least six hours of direct sunlight daily for optimal growth and flowering. Water deeply but infrequently, allowing the soil to dry out slightly between waterings. Fertilize sparingly in the spring with a balanced fertilizer to encourage healthy growth and bloom production. Prune back dead or damaged foliage in late winter or early spring before new growth emerges. Ensure good air circulation to prevent fungal diseases. Amend heavy clay soils with organic matter to improve drainage. Mulch around the base of the plant to retain moisture and suppress weeds. Monitor for pests and diseases and treat promptly. Repot container-grown grasses every few years to refresh the soil and provide more space for roots. Maintain moderate humidity levels, especially for indoor plants.

How do I propagate Ornamental Grass?

Ornamental grasses can be propagated through division. In early spring or fall, dig up the plant and carefully separate the root ball into smaller clumps. Each clump should have healthy roots and foliage. Replant the divisions in well-draining soil. Water thoroughly and keep the soil moist until new growth emerges. Stem cuttings are less common but can be taken in spring. Take 4-6 inch cuttings from new growth, remove lower leaves, and root in water or moist potting mix. Keikis (small plantlets that grow on the flower stalks) are rare but can be carefully removed and potted up. Provide bright, indirect light and consistent moisture to encourage rooting.

Peruvian Lily

What are the light requirements for Peruvian Lily?

Peruvian Lilies require at least six hours of sunlight per day to produce abundant blooms. A location with morning sun and afternoon shade is ideal, especially in hotter climates. Insufficient light can result in leggy growth and reduced flowering. When grown indoors, place them near a south-facing or east-facing window. Rotate the plant regularly to ensure even light exposure on all sides. If natural light is limited, supplement with grow lights to provide adequate illumination. Observe the plant’s growth patterns to determine if it’s receiving enough light. Pale or weak stems can indicate insufficient light.

How do I care for Peruvian Lily?

Peruvian Lilies thrive in well-draining soil and prefer a location with full sun to partial shade. Water thoroughly when the top inch of soil feels dry, but avoid overwatering to prevent root rot. Fertilize regularly during the growing season (spring and summer) with a balanced liquid fertilizer, focusing on a formula that encourages blooming. Deadhead spent flowers to promote continuous blooming. Provide support for taller varieties to prevent them from flopping over. Maintain moderate humidity levels. Repot when the plant becomes root-bound. Protect from frost in colder climates. Regularly inspect for pests and diseases. Ensure good air circulation to prevent fungal issues.

How do I propagate Peruvian Lily?

Peruvian Lilies can be propagated through division, stem cuttings, or keikis (small plantlets that grow on the stems). For division, carefully dig up the plant in early spring or fall and separate the rhizomes, ensuring each division has roots and shoots. Replant the divisions in well-draining soil. For stem cuttings, take 4-6 inch cuttings in the spring or summer, remove the lower leaves, and dip the cut end in rooting hormone. Plant the cuttings in a well-draining potting mix and keep them moist until rooted. Keikis can be carefully removed from the mother plant and potted separately. Provide adequate moisture and light for successful propagation.

Last updated: April 24, 2026 — Plant care data reviewed and verified by our editorial team.