Lemon Grass vs Sweet Pea 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
Sweet Pea

Sweet Pea

Lathyrus odoratus

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
Sweet Pea

Sweet Pea

Lathyrus odoratus

Sweet peas are annual climbing plants, known for their beautiful, fragrant flowers. They are not naturally indoor plants and are typically grown outdoors in gardens. They feature delicate, papery petals in a wide range of colors, including pink, purple, red, white, and bi-colors. Sweet peas climb using tendrils, reaching heights of 1 to 2 meters. People grow them for their ornamental value, the delightful fragrance of their blooms, and their use as cut flowers.

Fabaceae Sicily, Cyprus, Southern Italy, and the Aegean Islands
✨ Features: Highly fragrant flowers, attractive to pollinators.
📖 Read Complete Sweet Pea Guide

Quick Plant Comparison

Feature Lemon Grass Sweet Pea
Light Full sun (at least 6-8 hours of direct sunlight daily) Full sun (at least 6-8 hours of direct sunlight per day)
Watering Every 2-3 days during the growing season, less frequently in winter (every 7-10 days) Every 2-3 days outdoors, depending on weather conditions. Less frequent if grown indoors.
Humidity 40-60% 40-60%
Temperature 18-30°C 13-18°C
Care Level Expert Expert
Growth Rate Fast Fast
Max Height 0.6-1.2 meters (2-4 feet) indoors, up to 1.8 meters (6 feet) outdoors 1-2 meters (outdoors). Significantly smaller if grown indoors.
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining, loamy soil. A mix of potting soil, sand, and perlite is suitable. Well-draining, fertile soil rich in organic matter. A mix of garden soil, compost, and perlite is suitable.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 30 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.

Sweet Pea

Scientific Name Lathyrus odoratus
Family Fabaceae
Native To Sicily, Cyprus, Southern Italy, and the Aegean Islands
Also Known As Sweet Pea
Leaves The leaves are ovate to lanceolate, with a bluish-green color. They are arranged alternately along the stem and have prominent veins. The plant also produces tendrils that aid in climbing.
Flowers Sweet peas produce fragrant, papery flowers in a wide range of colors, including pink, purple, red, white, and bi-colors. They bloom profusely outdoors during the summer months. Flowering is rare and limited indoors.

📏 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.

Sweet Pea

Height 1-2 meters (outdoors). Significantly smaller if grown indoors.
Spread 30-60 cm
Growth Rate Fast
Growth Pattern Sweet peas are climbing annuals that use tendrils to attach to supports. They grow vertically, reaching heights of 1 to 2 meters outdoors. Indoors, growth is typically more constrained.

🌱 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.

Sweet Pea

Methods: Seed

Difficulty: Easy

Tips: Soak seeds in water for 24 hours before sowing to improve germination. Sow directly into the ground or in pots in early spring.

✨ 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

Sweet Pea

Sweet peas are known for their intense fragrance and wide range of colors. Their climbing habit and delicate petals make them a popular choice for cottage gardens and cut flower arrangements.

  • ✓ Beautiful and fragrant flowers
  • ✓ Attracts pollinators to the garden
  • ✓ Provides cut flowers for bouquets
  • ✓ Adds a touch of romance to the garden
  • ✓ Can be grown in a variety of colors
  • ⚠️ Toxic to pets

📅 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.

Sweet Pea

Repotting Not applicable as it's an annual. If grown indoors, repotting may be needed if the container is too small.
Pruning Pinch off the tips of young plants to encourage bushier growth. Deadhead spent flowers to promote continued blooming.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-3 weeks during the growing season.
Seasonal Care In spring, sow seeds and provide support for climbing. In summer, water regularly and fertilize. In fall, collect seeds for next year. In winter, the plant dies back as it is an annual.

🌞 Light Requirements

Lemon Grass

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

Low light tolerant: ❌ No

Sweet Pea

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

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.

Sweet Pea

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Ensure good drainage. Underwatering will cause wilting and reduced flowering.

🌡️ Temperature & Humidity

Lemon Grass

Temperature: 18-30°C

Humidity: 40-60%

Sweet Pea

Temperature: 13-18°C

Humidity: 40-60%

🤔 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.
Sweet Pea

Sweet Pea

Lathyrus odoratus
Care: Expert Time: 30 minutes weekly Beginner: No

Experienced gardeners who want to grow fragrant flowers outdoors.

✅ Choose This Plant If...

  • You love fragrant flowers and have a sunny outdoor garden.
  • You enjoy growing cut flowers for bouquets.
  • You want to attract pollinators to your garden.
  • You are an experienced gardener looking for a rewarding challenge.
  • You appreciate the wide variety of colors and forms available in sweet pea cultivars.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You lack a sunny outdoor space.
  • You are a beginner gardener looking for an easy-to-grow plant.
📍 Ideal Location: Sunny garden or balcony with support for climbing.
🎨 Style: Cottage, Romantic, Traditional
🏠 Apartment Friendly: Limited
⚠️ All parts of the sweet pea plant, especially the seeds, are toxic to dogs, cats, and horses. Symptoms include weakness, tremors, and seizures. Consult a veterinarian immediately if ingestion is suspected.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

☀️

Lemon Grass needs full sun (at least 6-8 hours of direct sunlight daily), while Sweet Pea prefers full sun (at least 6-8 hours of direct sunlight per day).

💡 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.

Sweet Pea Care Tips

Sweet peas are challenging to grow indoors due to their high light requirements and need for cool temperatures. They require consistent watering, fertilization, and support for climbing. Without ideal conditions, flowering will be limited.

  • Soak seeds overnight before planting to improve germination.
  • Provide a sturdy trellis or support for climbing.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Fertilize every 2-3 weeks during the growing season.
  • Protect from strong winds.
❄️ Winter: As an annual, the plant will die back in winter. Collect seeds for planting the following spring.
☀️ Summer: Provide regular watering and fertilization during the growing season. Protect from intense afternoon sun in hot climates. Deadhead spent flowers to encourage continued blooming.

⚠️ 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.

Sweet Pea

Common Issues: Powdery mildew, aphids, lack of flowering, root rot
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Aphids: Spray with insecticidal soap. Lack of flowering: Ensure adequate sunlight and fertilization. Root rot: Improve drainage and reduce watering frequency.

❓ 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.

Sweet Pea

What are the light requirements for Sweet Pea?

Sweet Peas require at least 6-8 hours of direct sunlight per day to thrive and produce abundant blooms. A south-facing location is ideal, especially in cooler climates. If growing indoors, place your Sweet Peas near a sunny window or use grow lights to supplement natural light. Insufficient light can lead to leggy growth, fewer flowers, and pale foliage. Rotate the plants regularly to ensure even light exposure. In hot climates, provide some afternoon shade to prevent scorching. Monitor the leaves for signs of sunburn, such as brown spots, and adjust the plant’s position accordingly. Good air circulation is also important to prevent fungal diseases that can be exacerbated by inadequate light.

How do I care for Sweet Pea?

Sweet Peas thrive in full sun and well-drained soil. Sow seeds directly into the ground in early spring or late fall, depending on your climate. Soaking the seeds overnight can improve germination. Provide a sturdy support system, such as a trellis or netting, for the vines to climb. Water regularly, especially during dry periods, and fertilize every 2-3 weeks with a balanced fertilizer to encourage abundant blooming. Deadhead spent flowers to promote continued flowering. Protect plants from pests like aphids and slugs. Ensure good air circulation to prevent fungal diseases. Sweet Peas prefer cooler temperatures, so provide shade during the hottest part of the day in warmer climates. Monitor for signs of powdery mildew and treat promptly. Proper staking and pruning are crucial for healthy growth and prolific blooms.

How do I propagate Sweet Pea?

Sweet Peas are primarily propagated by seed.

Last updated: April 19, 2026 — Plant care data reviewed and verified by our editorial team.