Lemon Grass vs Pennisetum Plant Comparison

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

Lemon Grass

Lemon Grass

Cymbopogon citratus

VS
Pennisetum

Pennisetum

Pennisetum setaceum

Lemon Grass

Lemon Grass

Cymbopogon citratus

Lemon Grass is a tall, perennial grass characterized by its fragrant, lemon-scented leaves and stalks. It typically grows in dense clumps, reaching heights of up to 1.8 meters (6 feet) outdoors. The plant is primarily cultivated for culinary and medicinal purposes, with its stalks and leaves used to flavor dishes, teas, and herbal remedies. While it can be grown indoors, it requires very bright light and may not thrive as well as it does outdoors. People grow it for its unique flavor and aroma, as well as its potential health benefits.

Poaceae Southeast Asia (India, Sri Lanka, Malaysia, Thailand)
✨ Features: Aromatic leaves, culinary uses, potential medicinal properties
📖 Read Complete Lemon Grass Guide
Pennisetum

Pennisetum

Pennisetum setaceum

Pennisetum setaceum is a perennial bunchgrass known for its graceful, arching foliage and bottlebrush-like flower spikes. Typically grown as an ornamental grass, it adds texture and movement to landscapes. The foliage can range from green to reddish-purple, with the flower plumes often appearing in shades of pink, purple, or white. It is primarily an outdoor plant, thriving in full sun and well-drained soil. People grow it for its aesthetic appeal, drought tolerance, and ability to attract birds.

Poaceae Tropical Africa, Southwest Asia, Arabian Peninsula
✨ Features: Drought tolerant, attracts birds, adds texture and movement to landscapes
📖 Read Complete Pennisetum Guide

Quick Plant Comparison

Feature Lemon Grass Pennisetum
Light Full sun (at least 6-8 hours of direct sunlight daily) Full sun (at least 6-8 hours of direct sunlight daily)
Watering Every 2-3 days during the growing season, less frequently in winter (every 7-10 days) Every 1-2 weeks, depending on weather and soil drainage
Humidity 40-60% 30-50%
Temperature 18-30°C 18-30°C
Care Level Expert Expert
Growth Rate Fast Moderate
Max Height 0.6-1.2 meters (2-4 feet) indoors, up to 1.8 meters (6 feet) outdoors Rarely grown indoors, outdoor height up to 1.2 meters
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining, loamy soil. A mix of potting soil, sand, and perlite is suitable. Well-drained soil, sandy or loamy
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 15 minutes weekly

🔬 Botanical Information — Comparing These Plants

Lemon Grass

Scientific Name Cymbopogon citratus
Family Poaceae
Native To Southeast Asia (India, Sri Lanka, Malaysia, Thailand)
Also Known As Lemon Grass, Lemongrass, Oil Grass, Fever Grass, Tanglad
Leaves The leaves of Lemon Grass are long, slender, and blade-like, typically reaching lengths of 30-90 cm (12-35 inches). They are a vibrant green color and have a slightly rough texture. The leaves have a prominent midrib and taper to a sharp point. When crushed, they release a strong lemon scent.
Flowers Lemon Grass rarely flowers indoors. Outdoors, it may produce flower spikes in warm climates, but flowering is infrequent and not the primary reason for cultivation. The flowers are small and inconspicuous.

Pennisetum

Scientific Name Pennisetum setaceum
Family Poaceae
Native To Tropical Africa, Southwest Asia, Arabian Peninsula
Also Known As Crimson Fountaingrass, Purple Fountaingrass
Leaves The leaves are long, narrow, and grass-like, typically green but can range to reddish-purple in some cultivars like 'Rubrum'. They have a slightly rough texture and arch gracefully.
Flowers It rarely flowers indoors. Outdoors, it produces bottlebrush-like flower spikes in shades of pink, purple, or white. The flowers are feathery and add to the plant's ornamental appeal.

📏 Size & Growth — Plant Comparison

Lemon Grass

Height 0.6-1.2 meters (2-4 feet) indoors, up to 1.8 meters (6 feet) outdoors
Spread 0.6-0.9 meters (2-3 feet), spreads via rhizomes
Growth Rate Fast
Growth Pattern Lemon Grass grows in dense clumps, with multiple stalks emerging from a central base. It has an upright growth habit, with leaves arching outwards. It spreads via rhizomes, which can lead to the formation of larger clumps over time.

Pennisetum

Height Rarely grown indoors, outdoor height up to 1.2 meters
Spread Up to 0.9 meters
Growth Rate Moderate
Growth Pattern It grows in a clumping or bunching habit, forming a dense mound of arching foliage. The flower spikes emerge from the center of the clump and rise above the foliage.

🌱 Propagation — Comparing Plant Growth

Lemon Grass

Methods: Division, Seed

Difficulty: Easy

Tips: Divide mature clumps in spring or summer. Ensure each division has healthy roots and shoots. Plant in well-draining soil and keep moist. Seeds can be sown indoors in early spring.

Pennisetum

Methods: Seed, Division

Difficulty: Easy

Tips: Divide clumps in spring or fall. Sow seeds in spring after the last frost.

✨ Benefits & Features — Comparing Plant Value

Lemon Grass

Lemon Grass is known for its distinct lemon scent and flavor, which is due to the presence of citronellal and geraniol. It is a fast-growing grass that can reach impressive heights under optimal conditions. Unlike many ornamental grasses, it is primarily grown for its culinary and medicinal uses.

  • ✓ Adds a unique flavor to culinary dishes
  • ✓ Provides a refreshing aroma
  • ✓ May have medicinal properties
  • ✓ Acts as a natural insect repellent
  • ✓ Enhances the aesthetic appeal of a garden or patio
  • ⚠️ Toxic to pets

Pennisetum

Its bottlebrush-like flower spikes and arching foliage create a graceful and dynamic appearance. The 'Rubrum' cultivar offers striking reddish-purple foliage, adding a unique color element to landscapes. It is also drought-tolerant once established.

  • ✓ Adds visual interest to gardens
  • ✓ Provides habitat for birds
  • ✓ Drought-tolerant, reducing water consumption
  • ✓ Low maintenance once established
  • ✓ Erosion control on slopes
  • 🐾 Pet Safe

📅 Maintenance Schedule — Plant Care Comparison

Lemon Grass

Repotting Every 1-2 years, or when the plant becomes root-bound. Divide the plant during repotting to control its spread.
Pruning Regularly trim dead or yellowing leaves. Cut back the plant in late winter or early spring to encourage new growth.
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, ensure adequate moisture and sunlight. Bring indoors before the first frost in colder climates.

Pennisetum

Repotting Not typically grown in pots long-term, but if container-grown, repot every 2-3 years.
Pruning Cut back dead or damaged foliage as needed. Prune in late winter/early spring to encourage new growth.
Fertilizing Balanced slow-release fertilizer in spring; avoid over-fertilizing
Seasonal Care Cut back foliage in late winter or early spring before new growth emerges. Reduce watering in winter.

🌞 Light Requirements

Lemon Grass

Full sun (at least 6-8 hours of direct sunlight daily)

Low light tolerant: ❌ No

Pennisetum

Full sun (at least 6-8 hours of direct sunlight daily)

Low light tolerant: ❌ No

💧 Watering Needs

Lemon Grass

Keep the soil consistently moist, but not waterlogged. Allow the top inch of soil to dry out slightly between waterings. Overwatering can lead to root rot, while underwatering will cause the leaves to dry out and turn brown. Ensure good drainage.

Pennisetum

Water deeply when the top inch of soil feels dry. Avoid overwatering, as this can lead to root rot. In containers, ensure proper drainage. During the growing season, water more frequently. Reduce watering in the winter.

🌡️ Temperature & Humidity

Lemon Grass

Temperature: 18-30°C

Humidity: 40-60%

Pennisetum

Temperature: 18-30°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Lemon Grass

Lemon Grass

Cymbopogon citratus
Care: Expert Time: 15 minutes weekly Beginner: No

Experienced gardeners who can provide ample sunlight and manage its growth.

✅ Choose This Plant If...

  • You want a fragrant herb for cooking and teas
  • You have a sunny outdoor space
  • You enjoy the challenge of growing plants that require specific conditions
  • You want a natural insect repellent
  • You are interested in the potential health benefits of Lemon Grass

❌ Skip This Plant If...

  • You have pets that may ingest it
  • You lack a very sunny location
  • You don't want to deal with a plant that spreads via rhizomes
📍 Ideal Location: Sunny patio, herb garden, or a very bright, south-facing window indoors
🎨 Style: Tropical, Bohemian, Natural
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Lemon Grass is toxic to dogs, cats, and horses. Symptoms include vomiting, diarrhea, and abdominal pain. The leaves are the primary toxic part.
Pennisetum

Pennisetum

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

Gardeners looking for drought-tolerant ornamental grasses for sunny locations.

✅ Choose This Plant If...

  • It adds beautiful texture and movement to gardens
  • It is drought-tolerant once established
  • It attracts birds to the garden
  • The 'Rubrum' cultivar provides striking reddish-purple foliage
  • It is relatively low-maintenance once established.

❌ Skip This Plant If...

  • It requires full sun and will not thrive indoors
  • It can be invasive in some regions
  • It needs well-drained soil and is susceptible to root rot if overwatered.
📍 Ideal Location: Outdoor garden or landscape in a sunny location
🎨 Style: Mediterranean, Southwestern, Modern
🏠 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 Pennisetum ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

📈

Lemon Grass has fast growth, while Pennisetum grows moderate.

💡 Pro Tips For Comparing These Plants

Lemon Grass Care Tips

Lemon Grass is primarily an outdoor plant that requires full sun and consistent moisture. Growing it indoors can be challenging due to its high light requirements. It also spreads via rhizomes, so it may outgrow its container quickly. Regular division and repotting are necessary.

  • Provide at least 6-8 hours of direct sunlight daily
  • Ensure well-draining soil to prevent root rot
  • Water deeply when the top inch of soil is dry
  • Fertilize regularly during the growing season
  • Divide the plant every 1-2 years to control its spread
❄️ Winter: In colder climates, bring Lemon Grass indoors before the first frost. Reduce watering frequency and provide as much light as possible. Avoid fertilizing during the winter months. Maintain temperatures above 10°C (50°F).
☀️ Summer: Ensure adequate moisture and sunlight during the summer months. Water deeply and regularly, especially during hot, dry periods. Fertilize every 2-4 weeks with a balanced liquid fertilizer. Protect from strong winds, which can damage the leaves.

Pennisetum Care Tips

Pennisetum setaceum is primarily an outdoor plant and is difficult to grow indoors due to its high light requirements. It needs full sun and well-drained soil. Overwintering indoors is possible in very bright locations, but plant will likely decline.

  • Plant in well-drained soil to prevent root rot.
  • Provide full sun for optimal growth and color.
  • Cut back foliage in late winter or early spring.
  • Monitor for pests and diseases regularly.
  • Avoid over-fertilizing, as this can lead to excessive growth.
❄️ Winter: Cut back foliage in late winter or early spring before new growth emerges. Reduce watering significantly during dormancy.
☀️ Summer: Water more frequently during hot, dry periods. Ensure adequate sunlight for optimal growth and color. Monitor for pests and diseases.

⚠️ Common Problems & Solutions — Plant Care Comparison

Lemon Grass

Common Issues: Root rot, spider mites, insufficient sunlight, brown leaf tips
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Spider mites: Increase humidity and treat with insecticidal soap. Insufficient sunlight: Move to a brighter location or supplement with grow lights. Brown leaf tips: Increase humidity and ensure consistent watering.

Pennisetum

Common Issues: Root rot, Rust, Aphids
Solutions: Ensure well-draining soil and avoid overwatering for root rot. Apply fungicide for rust. Use insecticidal soap for aphids.

❓ Frequently Asked Questions — Comparing These Plants

Lemon Grass

What are the light requirements for Lemon Grass?

Lemon Grass requires at least 6 hours of bright, indirect sunlight daily. Direct sunlight can scorch the leaves, so it’s best to place it near an east- or west-facing window where it receives filtered light. If you don’t have enough natural light, you can supplement with a grow light. Rotate the plant regularly to ensure even growth on all sides. Inadequate light can lead to leggy growth and reduced essential oil production, affecting the plant’s fragrance. Avoid placing Lemon Grass in a dark or shaded area.

How do I care for Lemon Grass?

Lemon Grass thrives in bright, indirect sunlight and requires well-draining soil. Water regularly, keeping the soil consistently moist but not waterlogged. During the growing season (spring and summer), fertilize monthly with a balanced liquid fertilizer. Prune regularly to maintain shape and encourage new growth. Lemon Grass prefers warm temperatures and high humidity; consider using a humidifier or placing the plant on a pebble tray filled with water. Repot annually in the spring to provide fresh soil and space for growth. Protect from frost and cold temperatures, as it is not cold-hardy. Monitor for pests such as aphids or spider mites and treat accordingly.

How do I propagate Lemon Grass?

Lemon Grass can be easily propagated through division, stem cuttings, or air layering. For division, carefully separate the plant into smaller clumps, ensuring each clump has healthy roots. For stem cuttings, take a 4-6 inch cutting from a healthy stem, remove the lower leaves, and plant it in moist soil. Keep the soil consistently moist until roots develop. For air layering, make a small cut on a stem, wrap it with moist sphagnum moss, and cover with plastic wrap. Once roots develop, cut the stem below the roots and plant it in soil. Propagation is best done in the spring or summer.

Pennisetum

What are the light requirements for Pennisetum?

Pennisetum requires at least 6-8 hours of direct sunlight per day to thrive and produce abundant flower plumes. Insufficient light can result in leggy growth, reduced flowering, and faded foliage color. When planting Pennisetum in the landscape, choose a location that receives full sun exposure throughout the day. If growing Pennisetum in containers, place them in a sunny spot on a patio or balcony. South-facing exposures are typically ideal. If you notice your Pennisetum is not flowering as expected, or if the foliage appears pale, consider moving it to a sunnier location. Supplemental lighting may be necessary in regions with short growing seasons or limited sunlight.

How do I care for Pennisetum?

Pennisetum thrives in full sun and well-draining soil. Water deeply but infrequently, allowing the soil to dry out slightly between waterings, especially once established. Fertilize in spring with a balanced, slow-release fertilizer to promote healthy growth and abundant blooms. Avoid over-fertilizing, as this can lead to excessive foliage growth at the expense of flowering. Prune back the foliage in late winter or early spring before new growth emerges. Remove any dead or damaged leaves throughout the growing season. Pennisetum is generally drought-tolerant once established but benefits from occasional watering during prolonged dry periods. Monitor for pests such as aphids or spider mites and treat accordingly. Provide adequate air circulation to prevent fungal diseases. Mulch around the base of the plant to help retain moisture and suppress weeds.

How do I propagate Pennisetum?

Pennisetum can be propagated by division or seed. Division is best done in spring. Dig up the plant and gently separate the root ball into smaller clumps, ensuring each clump has healthy roots and foliage. Replant the divisions in well-draining soil. To propagate by seed, sow seeds indoors in early spring or directly outdoors after the last frost. Keep the soil moist until germination occurs. Stem cuttings are not a common propagation method for Pennisetum. Keikis are not applicable as Pennisetum does not produce them. Provide ample sunlight and water regularly. Seedlings should be hardened off before transplanting outdoors.

Last updated: May 13, 2026 — Plant care data reviewed and verified by our editorial team.