Fountain Grass vs Giant Reed Plant Comparison

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

Fountain Grass

Fountain Grass

Pennisetum setaceum

VS
Giant Reed

Giant Reed

Arundo donax

Fountain Grass

Fountain Grass

Pennisetum setaceum

Fountain Grass is a perennial grass known for its graceful, arching foliage and bottlebrush-like flower plumes. Typically grown as an ornamental grass, it adds texture and movement to landscapes. It forms dense clumps of slender, linear leaves that can range in color from green to reddish-purple, depending on the cultivar. The feathery flower plumes emerge in summer and persist into fall, adding visual interest. While primarily an outdoor plant, it is sometimes grown in containers. It is valued for its drought tolerance and low maintenance requirements in suitable climates.

Poaceae Native to tropical Africa, Southwest Asia, and the Arabian Peninsula; naturalized in many other regions.
✨ Features: Drought tolerance, attractive flower plumes, adds texture and movement to landscapes.
📖 Read Complete Fountain Grass Guide
Giant Reed

Giant Reed

Arundo donax

Giant Reed is a tall, perennial grass characterized by its robust, cane-like stems and feathery plumes. It can reach heights of up to 6 meters (20 feet) or more. The plant spreads aggressively via rhizomes, forming dense thickets. While primarily an outdoor plant valued for erosion control, screening, and ornamental purposes, it is rarely grown indoors due to its size and high light requirements. Its rapid growth and invasive nature make it a challenging plant to manage.

Poaceae Native to the Mediterranean basin and parts of Asia; widely naturalized elsewhere
✨ Features: Rapid growth, effective erosion control, potential biofuel source, used in reed instruments.
📖 Read Complete Giant Reed Guide

Quick Plant Comparison

Feature Fountain Grass Giant Reed
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 1-2 weeks, depending on weather and soil drainage Every 1-2 weeks, depending on rainfall and soil drainage
Humidity 30-50% 30-50%
Temperature 18-30°C 15-30°C
Care Level Expert Expert
Growth Rate Fast Fast
Max Height 0.6-1.5 meters (outdoor); significantly smaller in containers indoors (if attempted) Not suitable for indoor growing; outdoors up to 6 meters (20 feet)
Pet Safety ✅ Safe ✅ Safe
Soil Well-draining soil, such as a sandy loam or a general-purpose potting mix amended with perlite. Well-draining soil; tolerates a wide range of soil types, including sandy, loamy, and clay soils. Prefers slightly acidic to neutral pH.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes monthly 30 minutes weekly (primarily for monitoring spread and pruning)

🔬 Botanical Information — Comparing These Plants

Fountain Grass

Scientific Name Pennisetum setaceum
Family Poaceae
Native To Native to tropical Africa, Southwest Asia, and the Arabian Peninsula; naturalized in many other regions.
Also Known As Fountain Grass, Crimson Fountain Grass, Purple Fountain Grass
Leaves Slender, linear leaves that can range in color from green to reddish-purple, depending on the cultivar. The leaves are typically 30-90 cm long and 0.5-1 cm wide.
Flowers Flowers are produced in bottlebrush-like plumes that can be pink, purple, or white. The plumes emerge in summer and persist into fall. It is very unlikely to flower indoors.

Giant Reed

Scientific Name Arundo donax
Family Poaceae
Native To Native to the Mediterranean basin and parts of Asia; widely naturalized elsewhere
Also Known As Giant Reed, Arundo, Spanish Reed, Carrizo
Leaves The leaves are long, lance-shaped, and typically green, although some cultivars may have variegated foliage. They are arranged alternately along the stem and have a rough texture.
Flowers Rarely flowers indoors. Outdoors, it produces large, feathery plumes of silvery-white flowers in late summer or early fall.

📏 Size & Growth — Plant Comparison

Fountain Grass

Height 0.6-1.5 meters (outdoor); significantly smaller in containers indoors (if attempted)
Spread 0.6-1.2 meters (outdoor); spreads via seeds and can be invasive in some regions.
Growth Rate Fast
Growth Pattern Forms dense clumps of arching, linear leaves. Flower plumes emerge from the center of the clump and arch outwards.

Giant Reed

Height Not suitable for indoor growing; outdoors up to 6 meters (20 feet)
Spread Spreads aggressively via rhizomes, forming large clumps. Can spread several meters wide.
Growth Rate Fast
Growth Pattern Upright, clumping growth habit. Spreads aggressively via rhizomes, forming dense thickets.

🌱 Propagation — Comparing Plant Growth

Fountain Grass

Methods: Seed, Division

Difficulty: Easy

Tips: Divide established clumps in spring or fall. Sow seeds in spring after the last frost. Ensure good drainage and consistent moisture during germination.

Giant Reed

Methods: Rhizome division, stem cuttings

Difficulty: Easy

Tips: Divide rhizomes in spring or fall. Stem cuttings can be rooted in water or directly in soil. Ensure adequate moisture during the rooting process.

✨ Benefits & Features — Comparing Plant Value

Fountain Grass

Fountain Grass is known for its graceful, arching foliage and bottlebrush-like flower plumes. The flower plumes add visual interest and movement to landscapes. Its drought tolerance makes it a popular choice for xeriscaping.

  • ✓ Adds visual interest to landscapes
  • ✓ Provides habitat for birds and beneficial insects
  • ✓ Drought-tolerant and low-maintenance
  • ✓ Erosion control on slopes
  • ✓ Can be used in cut flower arrangements
  • 🐾 Pet Safe

Giant Reed

Its rapid growth rate and tall stature distinguish it from other ornamental grasses. Its invasive nature requires careful management.

  • ✓ Rapid erosion control
  • ✓ Effective windbreak and privacy screen
  • ✓ Potential biofuel source
  • ✓ Natural sound barrier
  • ✓ Provides habitat for wildlife
  • 🐾 Pet Safe

📅 Maintenance Schedule — Plant Care Comparison

Fountain Grass

Repotting Not typically repotted if grown outdoors. If grown in containers, repot every 1-2 years in spring.
Pruning Cut back foliage in late winter or early spring before new growth emerges. Deadhead spent flower plumes to maintain appearance and prevent unwanted seed dispersal.
Fertilizing Apply a balanced slow-release fertilizer in spring. Avoid over-fertilizing, as this can lead to excessive foliage growth at the expense of flowering.
Seasonal Care In winter, cut back foliage to a few inches above the ground in colder climates. In summer, ensure adequate watering during dry spells.

Giant Reed

Repotting Not applicable for outdoor planting. If grown in a container (not recommended), repot annually to manage rhizome growth.
Pruning Prune to control size and shape. Remove dead or damaged stems regularly. Severe pruning can be done in late winter or early spring.
Fertilizing Apply a balanced slow-release fertilizer in spring. Avoid over-fertilizing, as it can encourage excessive growth.
Seasonal Care Cut back dead or damaged stems in late winter or early spring. Monitor for invasive spread throughout the growing season. Provide support during windy conditions.

🌞 Light Requirements

Fountain Grass

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

Low light tolerant: ❌ No

Giant Reed

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

Low light tolerant: ❌ No

💧 Watering Needs

Fountain Grass

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Allow the soil to dry out slightly between waterings. Signs of underwatering include drooping or browning leaves. Overwatering can cause yellowing leaves and a mushy base.

Giant Reed

Water deeply and regularly during the growing season, especially when newly planted. Established plants are relatively drought-tolerant but benefit from occasional watering during dry periods. Overwatering can lead to root rot, indicated by yellowing leaves and a foul odor from the soil. Underwatering results in wilting and browning of leaf tips.

🌡️ Temperature & Humidity

Fountain Grass

Temperature: 18-30°C

Humidity: 30-50%

Giant Reed

Temperature: 15-30°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Fountain Grass

Fountain Grass

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

Gardeners looking for a low-maintenance, ornamental grass to add texture and movement to their outdoor landscapes.

✅ Choose This Plant If...

  • You want a drought-tolerant ornamental grass for your garden.
  • You appreciate the graceful, arching foliage and feathery flower plumes.
  • You are looking for a low-maintenance plant that adds texture and movement to your landscape.
  • You live in a warm climate where it can thrive outdoors.
  • You want to attract birds to your garden.

❌ Skip This Plant If...

  • You live in a region where it is considered an invasive species.
  • You do not have a sunny outdoor space.
  • You are looking for a plant that thrives indoors.
📍 Ideal Location: Outdoor garden beds, borders, or containers in a sunny location.
🎨 Style: Mediterranean, Cottage, Modern, Naturalistic
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Pennisetum species are not listed as toxic to dogs, cats, or horses.
Giant Reed

Giant Reed

Arundo donax
Care: Expert Time: 30 minutes weekly (primarily for monitoring spread and pruning) Beginner: No

Landowners needing rapid erosion control or a tall privacy screen in suitable climates.

✅ Choose This Plant If...

  • You need a fast-growing screen or windbreak
  • You have a large area where you need erosion control
  • You live in a Mediterranean climate with plenty of sun
  • You are interested in experimenting with biofuel crops
  • You need a natural sound barrier for your property.

❌ Skip This Plant If...

  • You have a small garden or property
  • You live in an area where it is considered an invasive species
  • You are looking for a low-maintenance plant
  • You want an indoor plant
  • You have pets that might ingest large quantities of plant material.
📍 Ideal Location: Outdoors in a sunny location with ample space.
🎨 Style: Naturalistic, Mediterranean, Wild Garden
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Arundo donax is not listed as toxic to dogs, cats, or horses.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Both safe ✓
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

Fountain Grass Care Tips

Fountain Grass is primarily an outdoor plant that thrives in full sun and well-draining soil. Growing it indoors is challenging due to its high light requirements and potential size. It requires careful watering and fertilization. It can become invasive in some regions due to its prolific seed production.

  • Plant in well-draining soil to prevent root rot.
  • Provide full sun for optimal growth and flowering.
  • Water deeply but infrequently, allowing the soil to dry out slightly between waterings.
  • Cut back foliage in late winter or early spring to encourage new growth.
  • Deadhead spent flower plumes to prevent unwanted seed dispersal.
❄️ Winter: In colder climates, cut back foliage to a few inches above the ground in late winter or early spring. Mulch around the base of the plant to protect the roots from freezing temperatures.
☀️ Summer: Ensure adequate watering during dry spells. Deadhead spent flower plumes to maintain appearance and prevent unwanted seed dispersal. Monitor for pests and diseases.

Giant Reed Care Tips

Giant Reed is primarily an outdoor plant. Indoor cultivation is extremely challenging due to its size, light requirements, and aggressive growth. It needs full sun and ample space to thrive. Managing its invasive tendencies is crucial.

  • Plant in a location where its spread can be easily managed.
  • Provide regular watering during the establishment phase.
  • Monitor for signs of pests and diseases.
  • Cut back dead or damaged stems annually.
  • Consider using physical barriers to contain rhizome spread.
❄️ Winter: Cut back dead or damaged stems. Protect young plants from frost in colder climates.
☀️ Summer: Ensure adequate watering during hot, dry periods. Monitor for pests and diseases.

⚠️ Common Problems & Solutions — Plant Care Comparison

Fountain Grass

Common Issues: Root rot, Rust, Aphids, Seed dispersal (invasive potential)
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Rust: Improve air circulation and apply a fungicide if necessary. Aphids: Spray with insecticidal soap. Seed dispersal: Deadhead flower plumes before seeds mature to prevent unwanted spread.

Giant Reed

Common Issues: Invasive spread, susceptibility to aphids, fungal diseases in humid conditions, lodging (falling over) in strong winds.
Solutions: Use physical barriers to contain rhizome spread. Treat aphids with insecticidal soap. Improve air circulation to prevent fungal diseases. Provide support or prune to prevent lodging.

❓ Frequently Asked Questions — Comparing These Plants

Fountain Grass

What are the light requirements for Fountain Grass?

Fountain Grass requires a minimum of six hours of direct sunlight each day to thrive and produce abundant blooms. Insufficient light can lead to weak growth, fewer flowers, and a generally unhealthy appearance. When planting Fountain Grass, choose a location that receives full sun exposure throughout the day.

How do I care for Fountain Grass?

Fountain Grass thrives in full sun and well-drained soil. Water deeply but infrequently, allowing the soil to dry out slightly between waterings. Fertilize in spring with a balanced fertilizer to promote healthy growth and abundant blooms. Prune back dead foliage in late winter or early spring before new growth emerges.

How do I propagate Fountain Grass?

Fountain Grass is easily propagated by division. In early spring, carefully dig up the clump and divide it into smaller sections, ensuring each section has healthy roots and foliage. Replant the divisions in well-drained soil and water thoroughly. Stem cuttings are not a reliable method. Keikis do not naturally occur on Fountain Grass.

Giant Reed

What are the light requirements for Giant Reed?

Giant Reed requires at least 6-8 hours of direct sunlight per day to thrive. Insufficient light can lead to weak growth, leggy stems, and reduced flowering. When planting in a container, choose a location that receives full sun throughout the day. If growing indoors, a south-facing window is ideal. Supplemental lighting, such as grow lights, may be necessary if natural light is limited. Rotate the plant regularly to ensure even light exposure on all sides. Observe the plant’s growth and adjust its position as needed to maximize sunlight absorption.

How do I care for Giant Reed?

Giant Reed thrives in full sun and prefers consistently moist to wet conditions. If grown in a container, use a large pot with drainage holes and place it in a tray filled with water to ensure constant moisture. For in-ground planting, choose a location near a water source or amend the soil with plenty of organic matter to improve water retention. Fertilize monthly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Prune dead or damaged stems regularly to maintain its appearance and prevent overcrowding. Monitor for pests and diseases, and address any issues promptly. Provide winter protection in colder climates by mulching around the base of the plant. Maintain good water quality by regularly changing water in containers and ensuring adequate circulation in ponds.

How do I propagate Giant Reed?

Giant Reed is easily propagated through division or cuttings. For division, carefully dig up a mature clump and separate it into smaller sections, ensuring each section has healthy roots and stems. Replant the divisions in separate containers or directly into the ground. For cuttings, take 6-8 inch stem cuttings in spring or summer. Place the cuttings in water, ensuring that the nodes are submerged. Roots should develop within a few weeks. Once roots are established, transplant the cuttings into pots filled with moist soil or directly into the ground near a water source. Keep the soil consistently moist until the plants are well-established.

Last updated: May 12, 2026 — Plant care data reviewed and verified by our editorial team.