Citronella vs Pencil Cactus Plant Comparison

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

Citronella

Citronella

Cymbopogon nardus or Cymbopogon winterianus

VS
Pencil Cactus

Pencil Cactus

Euphorbia tirucalli

Citronella

Citronella

Cymbopogon nardus or Cymbopogon winterianus

Citronella is a perennial clumping grass known for its distinct citrusy scent, primarily due to the presence of citronellal and geraniol in its leaves. It typically grows to a height of 3-6 feet. It's primarily grown outdoors for its mosquito-repelling properties, although the effectiveness is debated and requires crushing the leaves to release the oils. It is not naturally an indoor plant and requires very specific conditions to thrive indoors.

Poaceae (Grass family) Asia (Sri Lanka, India, Indonesia)
✨ Features: Citrus-scented foliage, mosquito-repelling properties (when crushed).
📖 Read Complete Citronella Guide
Pencil Cactus

Pencil Cactus

Euphorbia tirucalli

Euphorbia tirucalli, commonly known as Pencil Cactus, is a succulent shrub or small tree characterized by its smooth, cylindrical, pencil-thick green branches. It is virtually leafless for most of the year, with small, inconspicuous leaves appearing only briefly during the growing season. This plant can reach significant heights outdoors, but remains smaller when grown in containers. It's popular for its unique architectural form and drought tolerance. People grow it for its sculptural qualities and low maintenance requirements. It is primarily an outdoor plant but can be grown indoors with proper care.

Euphorbiaceae East Africa, India
✨ Features: Unique sculptural form, drought tolerance
📖 Read Complete Pencil Cactus Guide

Quick Plant Comparison

Feature Citronella Pencil Cactus
Light Full sun (at least 6-8 hours of direct sunlight daily) Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth and color.
Watering Every 3-7 days depending on weather and soil drainage. Every 2-4 weeks, depending on environmental conditions and pot size.
Humidity 40-60% 30-50%
Temperature 18-30°C 18-27°C
Care Level Expert Moderate
Growth Rate Fast Moderate
Max Height 1-2 meters outdoors, significantly smaller indoors (0.3-0.6 meters) 1-2 meters indoors, up to 7 meters outdoors
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining loamy soil Well-draining succulent or cactus mix
Beginner Friendly ❌ No With Caution
Weekly Maintenance 15 minutes weekly 5-10 minutes bi-weekly

🔬 Botanical Information — Comparing These Plants

Citronella

Scientific Name Cymbopogon nardus or Cymbopogon winterianus
Family Poaceae (Grass family)
Native To Asia (Sri Lanka, India, Indonesia)
Also Known As Citronella grass, Nardus grass, Mana grass
Leaves The leaves are long, slender, and green, with a rough texture. They are typically 1-3 cm wide and up to 1 meter long. When crushed, the leaves release a strong citrus scent.
Flowers Citronella rarely flowers indoors. Outdoors, it produces panicles of small, inconspicuous flowers.

Pencil Cactus

Scientific Name Euphorbia tirucalli
Family Euphorbiaceae
Native To East Africa, India
Also Known As Pencil Cactus, Milk Bush, Indian Tree Spurge, Sticks on Fire
Leaves Leaves are small, lance-shaped, and inconspicuous, appearing only briefly during the growing season. They are typically less than 1 cm long and quickly fall off, leaving the plant virtually leafless.
Flowers It rarely flowers indoors. Outdoors, it produces small, inconspicuous yellow flowers at the tips of the branches, but flowering is infrequent.

📏 Size & Growth — Plant Comparison

Citronella

Height 1-2 meters outdoors, significantly smaller indoors (0.3-0.6 meters)
Spread 0.5-1 meter, clumping growth habit
Growth Rate Fast
Growth Pattern Citronella grows in clumps, with upright stems reaching several feet in height. It spreads through rhizomes, but is not considered highly invasive.

Pencil Cactus

Height 1-2 meters indoors, up to 7 meters outdoors
Spread 0.5-1 meter indoors, up to 2 meters outdoors
Growth Rate Moderate
Growth Pattern Upright, branching succulent shrub or small tree. It grows vertically with numerous cylindrical branches emerging from the main stem, creating a dense, bushy appearance.

🌱 Propagation — Comparing Plant Growth

Citronella

Methods: Division, Seed

Difficulty: Easy

Tips: Divide established clumps in spring or early summer. Ensure each division has healthy roots and shoots. Plant in well-draining soil and water thoroughly.

Pencil Cactus

Methods: Stem cuttings

Difficulty: Easy

Tips: Allow the cut end to callus over for several days before planting in well-draining soil. Wear gloves to avoid skin irritation from the sap.

✨ Benefits & Features — Comparing Plant Value

Citronella

The strong citrus scent is the most unique characteristic. The plant's mosquito-repelling properties, though debated, are also a key feature. It is a fast-growing grass that can quickly fill in garden spaces.

  • ✓ Natural mosquito repellent (when crushed)
  • ✓ Pleasant citrus scent
  • ✓ Fast-growing ground cover
  • ✓ Adds texture and movement to the garden
  • ✓ Relatively easy to propagate
  • ⚠️ Toxic to pets

Pencil Cactus

Its unique pencil-like branches and minimal foliage give it a distinct architectural appearance. The plant's drought tolerance and ability to thrive in harsh conditions make it a resilient and low-maintenance choice.

  • ✓ Drought-tolerant and low-maintenance
  • ✓ Adds a unique sculptural element to indoor spaces
  • ✓ Can improve indoor air quality by absorbing carbon dioxide
  • ✓ Provides a visually interesting focal point
  • ✓ Relatively pest-resistant when properly cared for
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Citronella

Repotting Repot every 1-2 years in spring if grown in a container, or when the plant becomes root-bound.
Pruning Trim dead or yellowing leaves regularly. 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 4-6 weeks during the growing season (spring/summer).
Seasonal Care During the growing season (spring/summer), water more frequently and fertilize regularly. In winter, reduce watering and withhold fertilizer. Protect from frost.

Pencil Cactus

Repotting Every 2-3 years, or when the plant becomes root-bound.
Pruning Prune to maintain shape and remove dead or damaged branches. Wear gloves and eye protection when pruning to avoid contact with the sap.
Fertilizing Balanced liquid fertilizer diluted to half strength, applied once in spring and once in summer.
Seasonal Care Reduce watering in winter during dormancy. Provide bright light year-round. Protect from frost.

🌞 Light Requirements

Citronella

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

Low light tolerant: ❌ No

Pencil Cactus

Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth and color.

Low light tolerant: ❌ No

💧 Watering Needs

Citronella

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Allow soil to drain freely. Signs of underwatering include drooping or browning leaves. Overwatering can cause yellowing leaves and a musty smell from the soil.

Pencil Cactus

Allow the soil to dry out completely between waterings. Water thoroughly when the soil is dry to the touch. Reduce watering frequency during the dormant winter months. Overwatering can lead to root rot. Signs of underwatering include shriveled branches. Signs of overwatering include yellowing or mushy branches.

🌡️ Temperature & Humidity

Citronella

Temperature: 18-30°C

Humidity: 40-60%

Pencil Cactus

Temperature: 18-27°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Citronella

Citronella

Cymbopogon nardus or Cymbopogon winterianus
Care: Expert Time: 15 minutes weekly Beginner: No

Gardeners with outdoor space looking for a natural mosquito repellent (though effectiveness is limited).

✅ Choose This Plant If...

  • You want a natural mosquito repellent for your garden (though effectiveness is limited).
  • You enjoy the citrusy scent of the foliage.
  • You have a sunny outdoor space.
  • You are experienced with plant care and can provide the specific conditions needed.
  • You want a fast-growing grass for your garden.

❌ Skip This Plant If...

  • You don't have a sunny outdoor space.
  • You have pets that might ingest the plant.
  • You are looking for a low-maintenance indoor plant.
  • You are sensitive to strong scents.
  • You live in a climate with harsh winters.
📍 Ideal Location: Sunny outdoor garden or patio.
🎨 Style: Tropical, Naturalistic
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, citronella contains essential oils that are toxic to dogs, cats, and horses. Symptoms include vomiting, diarrhea, increased salivation, and dermatitis.
Pencil Cactus

Pencil Cactus

Euphorbia tirucalli
Care: Moderate Time: 5-10 minutes bi-weekly Beginner: With-caution

Experienced plant owners who want a unique, sculptural succulent and can provide ample sunlight and keep it away from pets and children.

✅ Choose This Plant If...

  • You want a visually striking, low-maintenance plant.
  • You have a sunny location where it can thrive.
  • You are experienced with succulents and understand their watering needs.
  • You don't have pets or small children who might be exposed to the toxic sap.
  • You appreciate unique and sculptural plants.

❌ Skip This Plant If...

  • You have pets or small children due to the plant's toxicity.
  • You cannot provide adequate sunlight.
  • You tend to overwater plants.
  • You are looking for a plant that is easy to propagate without special precautions.
📍 Ideal Location: South-facing window or sunroom
🎨 Style: Modern, Minimalist, Southwestern
🏠 Apartment Friendly: Limited
⚠️ All parts of the plant contain a milky sap that is toxic to dogs, cats, and horses. Contact with the sap can cause skin irritation, oral irritation, vomiting, and diarrhea. Eye contact can cause severe irritation and temporary blindness.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

🎯

Citronella is rated Expert care level, while Pencil Cactus is Moderate.

📈

Citronella has fast growth, while Pencil Cactus grows moderate.

💡 Pro Tips For Comparing These Plants

Citronella Care Tips

Citronella is primarily an outdoor plant. Growing it indoors is challenging due to its high light requirements. It needs full sun, well-draining soil, and careful watering to avoid root rot. It is also toxic to pets, so keep it out of reach.

  • Plant in well-draining soil to prevent root rot.
  • Provide at least 6-8 hours of direct sunlight daily.
  • Water deeply but infrequently, allowing the soil to dry out slightly between waterings.
  • Fertilize regularly during the growing season.
  • Protect from frost in colder climates.
❄️ Winter: In colder climates, protect citronella from frost by bringing it indoors (though it will likely struggle) or covering it with a frost blanket. Reduce watering significantly.
☀️ Summer: Water more frequently during the summer months, especially during hot, dry weather. Fertilize regularly to promote healthy growth. Ensure adequate sunlight.

Pencil Cactus Care Tips

Pencil Cactus requires bright light and infrequent watering. It is relatively easy to care for, but its toxic sap makes it unsuitable for homes with pets or small children. Indoor growth requires careful attention to light and watering to prevent etiolation and root rot.

  • Provide at least 6 hours of direct sunlight daily.
  • Allow the soil to dry out completely between waterings.
  • Use a well-draining succulent mix to prevent root rot.
  • Wear gloves and eye protection when handling the plant to avoid contact with the toxic sap.
  • Avoid over-fertilizing, as this can lead to leggy growth.
❄️ Winter: Reduce watering significantly during the winter months as the plant enters a dormant period. Ensure the plant is still receiving adequate sunlight. Protect from frost.
☀️ Summer: Water more frequently during the summer growing season, but still allow the soil to dry out completely between waterings. Provide ample sunlight and good ventilation.

⚠️ Common Problems & Solutions — Plant Care Comparison

Citronella

Common Issues: Root rot, spider mites, insufficient sunlight
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Spider mites: Treat with insecticidal soap or neem oil. Insufficient sunlight: Provide supplemental lighting or move the plant outdoors during the growing season.

Pencil Cactus

Common Issues: Root rot, scale insects, mealybugs, etiolation (stretching due to insufficient light)
Solutions: Root rot: Improve drainage and reduce watering frequency. Scale insects/Mealybugs: Treat with insecticidal soap or neem oil. Etiolation: Provide more light.

❓ Frequently Asked Questions — Comparing These Plants

Citronella

What are the light requirements for Citronella?

Citronella plants need a good amount of sunlight to thrive. Aim for at least 6 hours of direct sunlight per day for optimal growth and mosquito-repelling potency. If growing indoors, place the plant near a sunny window, preferably south-facing. If natural light is insufficient, supplement with grow lights.

How do I care for Citronella?

Citronella plants thrive in well-draining soil and prefer full sun to partial shade. Water regularly, allowing the soil to dry slightly between waterings. Avoid overwatering, which can lead to root rot. Fertilize every 4-6 weeks during the growing season (spring and summer) with a balanced fertilizer to promote healthy growth and flowering.

How do I propagate Citronella?

Citronella can be propagated through several methods. Division involves separating the plant into smaller clumps and repotting them. Stem cuttings can be taken from healthy stems and rooted in water or soil. Keikis, or baby plants, sometimes form on mature plants and can be carefully removed and potted.

Pencil Cactus

What are the light requirements for Pencil Cactus?

Pencil Cactus thrives in bright, direct sunlight. Aim for at least 6 hours of direct sunlight per day. Insufficient light can cause etiolation, resulting in weak, pale growth. An east- or south-facing window is ideal. If natural light is limited, supplement with a grow light. Rotate the plant regularly to ensure even light exposure on all sides.

How do I care for Pencil Cactus?

Pencil Cactus is a relatively easy-to-care-for succulent, thriving on neglect and bright light. Plant in well-draining cactus mix. Water sparingly, allowing the soil to dry out completely between waterings, especially during winter dormancy. Provide at least 6 hours of direct sunlight daily.

How do I propagate Pencil Cactus?

Pencil Cactus can be easily propagated through stem cuttings. Allow the cut end to callus over for several days before planting in well-draining cactus mix. Keep the soil slightly moist until roots develop. Propagation from offsets is also possible; simply detach the offset and plant it in well-draining soil. Seed propagation is more challenging and requires patience. Grafting is less common but can be used to propagate difficult-to-root varieties. Always wear gloves when handling cuttings due to the irritating sap. Allow the cutting to dry and form a callous before planting in soil. Protect from excessive sun while rooting. Rooting hormone can be used, but is not necessary.

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