Ornamental Grass vs Purple Passionflower 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
Purple Passionflower

Purple Passionflower

Passiflora incarnata

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
Purple Passionflower

Purple Passionflower

Passiflora incarnata

Passiflora incarnata, commonly known as Purple Passionflower or Maypop, is a perennial climbing vine known for its intricate and beautiful flowers. It is primarily an outdoor plant, thriving in sunny locations. The vine produces edible fruit (though not always palatable). People grow it for its ornamental value, attracting pollinators like butterflies and bees, and for its potential medicinal properties (though use requires caution and research). While it can be grown indoors, it requires very bright light and is unlikely to thrive as well as outdoors.

Passifloraceae Southeastern United States, Mexico, Central America
✨ Features: Attracts pollinators, edible fruit (though flavor varies), potential medicinal properties (use with caution).
📖 Read Complete Purple Passionflower Guide

Quick Plant Comparison

Feature Ornamental Grass Purple Passionflower
Light Full sun (at least 6 hours of direct sunlight daily) Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal flowering and growth.
Watering Every 1-2 weeks, depending on environmental conditions and pot size Every 3-7 days, depending on environmental conditions and soil drainage.
Humidity 30-50% 40-60%
Temperature 18-27°C 18-27°C
Care Level Expert Expert
Growth Rate Moderate Fast
Max Height 0.6-1.2 meters (indoors, typically smaller) Indoors: 1-2 meters (difficult to manage). Outdoors: 3-9 meters.
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil Well-draining soil; a mix of potting soil, sand, and perlite is suitable Well-draining soil, such as a mix of potting soil, perlite, and compost.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 30-60 minutes weekly (pruning, watering, pest control).

🔬 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.

Purple Passionflower

Scientific Name Passiflora incarnata
Family Passifloraceae
Native To Southeastern United States, Mexico, Central America
Also Known As Purple Passionflower, Maypop, Apricot Vine
Leaves The leaves are typically three-lobed, deep green, and 10-15 cm long. They have serrated edges and a slightly rough texture.
Flowers It can flower indoors with sufficient light, but it's more common outdoors. The flowers are large (7-10 cm in diameter) with white or pink petals, a purple and white fringed corona, and prominent stamens and pistils.

📏 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.

Purple Passionflower

Height Indoors: 1-2 meters (difficult to manage). Outdoors: 3-9 meters.
Spread Spreads aggressively via rhizomes. Can easily take over a garden if not contained.
Growth Rate Fast
Growth Pattern Climbing vine that spreads rapidly via rhizomes. It can quickly cover a trellis or fence.

🌱 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.

Purple Passionflower

Methods: Stem cuttings, Seed, Root division

Difficulty: Easy

Tips: Take stem cuttings in spring or summer. Root in water or directly in moist soil. For seeds, scarify and soak them before planting.

✨ 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

Purple Passionflower

The intricate and exotic-looking flowers are its most distinctive feature. It's also known for its aggressive growth habit and potential medicinal uses.

  • ✓ Attracts pollinators like butterflies and bees
  • ✓ Provides visual interest with its unique flowers
  • ✓ Offers potential edible fruit (though flavor varies)
  • ✓ May have medicinal properties (with caution and research)
  • ✓ Can provide shade and privacy when grown on a trellis
  • ⚠️ 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.

Purple Passionflower

Repotting If grown in a container, repot annually in spring. Choose a large pot to accommodate its root system.
Pruning Prune regularly to control its size and shape. Remove dead or damaged growth. Prune after flowering to encourage bushier growth.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 4-6 weeks during the growing season (spring and summer).
Seasonal Care In winter, reduce watering and fertilizing. Provide protection from frost in colder climates. Prune in late winter or early spring to encourage new growth.

🌞 Light Requirements

Ornamental Grass

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

Low light tolerant: ❌ No

Purple Passionflower

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

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.

Purple Passionflower

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Signs of underwatering include wilting leaves and dry soil. Overwatering symptoms include yellowing leaves and soggy soil.

🌡️ Temperature & Humidity

Ornamental Grass

Temperature: 18-27°C

Humidity: 30-50%

Purple Passionflower

Temperature: 18-27°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.
Purple Passionflower

Purple Passionflower

Passiflora incarnata
Care: Expert Time: 30-60 minutes weekly (pruning, watering, pest control). Beginner: No

Experienced gardeners who want an ornamental vine for their outdoor space and are aware of its aggressive spreading habit.

✅ Choose This Plant If...

  • You have a sunny outdoor space and want to attract pollinators.
  • You are looking for a fast-growing vine to cover a trellis or fence.
  • You are interested in the potential medicinal properties of the plant (with proper research and caution).
  • You want to grow your own edible fruit (though flavor can vary).
  • You enjoy the unique and intricate beauty of the passionflower.

❌ Skip This Plant If...

  • You have limited sunlight indoors.
  • You have pets that might ingest the plant.
  • You don't want a plant that spreads aggressively.
  • You are a beginner gardener looking for an easy indoor plant.
📍 Ideal Location: Outdoors: Sunny garden, trellis, fence. Indoors: South-facing window with supplemental lighting.
🎨 Style: Bohemian, Cottagecore, Tropical
🏠 Apartment Friendly: No
⚠️ The ASPCA lists Passiflora species as toxic to dogs, cats, and horses. Symptoms include dilated pupils, tremors, and incoordination. All parts of the plant are potentially toxic.

🎯 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 Purple Passionflower grows fast.

💡 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.

Purple Passionflower Care Tips

Purple Passionflower is primarily an outdoor plant. Indoor cultivation is challenging due to its high light requirements and aggressive growth habit. It needs regular pruning and a large trellis. Expect limited flowering indoors. It is also toxic to pets.

  • Provide a strong support structure for the vine to climb.
  • Water deeply but infrequently, allowing the soil to dry slightly between waterings.
  • Fertilize regularly during the growing season to promote flowering.
  • Prune aggressively to control its spread and maintain its shape.
  • Monitor for pests and diseases regularly and treat promptly.
❄️ Winter: Reduce watering and fertilizing during the winter months. Provide protection from frost in colder climates. Prune in late winter or early spring.
☀️ Summer: Water more frequently during the summer months, especially during hot and dry periods. Provide shade during the hottest part of the day to prevent leaf scorch. Fertilize regularly to promote flowering.

⚠️ 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.

Purple Passionflower

Common Issues: Spider mites, Aphids, Root rot, Lack of flowering
Solutions: Spider mites/Aphids: Insecticidal soap or neem oil. Root rot: Improve drainage, reduce watering. Lack of flowering: Provide more sunlight, fertilize appropriately.

❓ 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.

Purple Passionflower

What are the light requirements for Purple Passionflower?

Purple Passionflower thrives in bright, direct sunlight. Aim for at least 6 hours of sunlight per day for optimal growth and abundant flowering. If grown indoors, place it near a south-facing window where it can receive ample sunlight. If sufficient natural light is not available, supplement with grow lights.

How do I care for Purple Passionflower?

Provide your Purple Passionflower with at least 6 hours of direct sunlight daily for optimal blooming. Water thoroughly when the top inch of soil feels dry, ensuring good drainage to prevent root rot. Fertilize regularly with a balanced fertilizer during the growing season (spring and summer) to encourage abundant flowering. Prune lightly to control its growth and remove any dead or damaged vines.

How do I propagate Purple Passionflower?

Purple Passionflower can be easily propagated through stem cuttings. Take a 4-6 inch cutting from a healthy stem, removing the lower leaves. Dip the cut end in rooting hormone and plant in a well-draining potting mix. Keep the soil moist and provide bright, indirect light. Roots should develop in a few weeks.

Last updated: May 9, 2026 — Plant care data reviewed and verified by our editorial team.