Cockscomb vs Purple Fountain Grass Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Cockscomb
Celosia cristata
Celosia cristata, commonly known as Cockscomb, is an annual plant prized for its uniquely shaped flower heads that resemble a rooster's comb. These vibrant blooms come in various colors, including red, pink, orange, yellow, and purple. It is primarily an outdoor plant, grown in gardens and containers for its ornamental value. Celosia thrives in warm weather and full sun, adding a splash of color to landscapes. While it can be attempted indoors, maintaining optimal conditions for flowering is challenging.
Purple Fountain Grass
Pennisetum setaceum 'Rubrum'
Purple Fountain Grass is a striking ornamental grass prized for its arching, burgundy-purple foliage and bottlebrush-like flower plumes. It typically grows in a mounded form, reaching several feet in height and width. While technically a perennial in warmer climates, it is often grown as an annual in cooler regions due to its sensitivity to frost. It is primarily an outdoor plant, grown for its dramatic texture and color in gardens and landscapes. People grow it for its ornamental value, adding movement and visual interest to borders, containers, and mass plantings.
Quick Plant Comparison
| Feature | Cockscomb | Purple Fountain Grass |
|---|---|---|
| Light | Full sun (at least 6-8 hours of direct sunlight daily) | Full sun (at least 6 hours of direct sunlight per day) |
| Watering | Every 2-3 days outdoors during hot weather; less frequently indoors depending on light and temperature. | Every 7-10 days, depending on weather and soil drainage |
| Humidity | 40-60% | 20-50% |
| Temperature | 21-27°C | 18-30°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | Indoors: 30-60 cm (1-2 feet); Outdoors: 30-90 cm (1-3 feet) | Outdoor: 0.6-1.5 meters. Indoor (unlikely to thrive): 0.3-0.6 meters |
| Pet Safety | ❌ Toxic To Pets | ✅ Safe |
| Soil | Well-draining potting mix or garden soil enriched with organic matter | Well-draining soil, such as a sandy loam or a potting mix amended with perlite |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 10 minutes weekly | 15 minutes weekly |
🔬 Botanical Information — Comparing These Plants
Cockscomb
| Scientific Name | Celosia cristata |
|---|---|
| Family | Amaranthaceae |
| Native To | Tropical Africa, possibly India |
| Also Known As | Cockscomb, Crested Celosia, Woolflower |
| Leaves | The leaves of Celosia are lance-shaped to oval, typically 5-15 cm (2-6 inches) long and 2-5 cm (1-2 inches) wide. They are usually green, but some varieties may have reddish or purplish hues. The leaves have a smooth texture and prominent veins. |
| Flowers | Celosia cristata produces vibrant and uniquely shaped flower heads. The crested varieties have a dense, velvety texture and resemble a rooster's comb. The flowers come in a range of colors, including red, pink, orange, yellow, and purple. Flowering is unlikely indoors without supplemental lighting. |
Purple Fountain Grass
| Scientific Name | Pennisetum setaceum 'Rubrum' |
|---|---|
| Family | Poaceae |
| Native To | Hybrid cultivar; species native to Africa, Southwest Asia |
| Also Known As | Purple Fountain Grass, Red Fountain Grass |
| Leaves | The leaves are long, narrow, and arching, with a deep burgundy-purple color. They have a fine texture and create a graceful, flowing appearance. |
| Flowers | It produces bottlebrush-like flower plumes that are initially a deep burgundy-purple, fading to a tan color as they mature. Flowering typically occurs in summer and fall. It is unlikely to flower indoors. |
📏 Size & Growth — Plant Comparison
Cockscomb
Purple Fountain Grass
🌱 Propagation — Comparing Plant Growth
Cockscomb
Methods: Seed
Difficulty: Easy
Tips: Sow seeds indoors 6-8 weeks before the last frost or directly outdoors after the danger of frost has passed. Seeds require light to germinate, so press them gently into the soil surface.
Purple Fountain Grass
Methods: Seed, Division
Difficulty: Moderate
Tips: Divide clumps in spring or early summer. Sow seeds indoors 6-8 weeks before the last frost.
✨ Benefits & Features — Comparing Plant Value
Cockscomb
Celosia's most striking feature is its unusual flower head, which comes in various shapes and colors. The crested varieties resemble a rooster's comb, while others have feathery or wheat-like blooms. This unique appearance makes it a popular choice for adding visual interest to gardens.
- ✓ Adds vibrant color to gardens
- ✓ Attracts pollinators
- ✓ Provides unique visual interest
- ✓ Edible flowers (though not recommended due to toxicity to pets)
- ✓ Relatively easy to grow outdoors
- ⚠️ Toxic to pets
Purple Fountain Grass
Its deep purple foliage and graceful, arching habit make it a standout in any garden. The bottlebrush-like flower plumes add further visual interest and movement.
- ✓ Adds visual interest and texture to the garden
- ✓ Attracts birds
- ✓ Drought tolerant
- ✓ Deer resistant
- ✓ Provides movement in the landscape
- 🐾 Pet Safe
📅 Maintenance Schedule — Plant Care Comparison
Cockscomb
Purple Fountain Grass
🌞 Light Requirements
Cockscomb
Full sun (at least 6-8 hours of direct sunlight daily)
Low light tolerant: ❌ No
Purple Fountain Grass
Full sun (at least 6 hours of direct sunlight per day)
Low light tolerant: ❌ No
💧 Watering Needs
Cockscomb
Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Ensure good drainage. Reduce watering frequency during cooler periods.
Purple Fountain Grass
Water deeply when the top inch of soil feels dry to the touch. Avoid overwatering, which can lead to root rot. Signs of underwatering include drooping or browning leaves. Signs of overwatering include yellowing leaves and soggy soil.
🌡️ Temperature & Humidity
Cockscomb
Temperature: 21-27°C
Humidity: 40-60%
Purple Fountain Grass
Temperature: 18-30°C
Humidity: 20-50%
🤔 Which Plant Is Right For You?
Cockscomb
Celosia cristataGardeners looking for vibrant, uniquely shaped flowers to add to their outdoor landscapes.
✅ Choose This Plant If...
- You want a vibrant, eye-catching flower in your garden.
- You enjoy unique and unusual plant shapes.
- You have a sunny outdoor space.
- You want to attract pollinators to your garden.
- You are looking for a relatively low-maintenance annual flower.
❌ Skip This Plant If...
- You have pets that might ingest the plant.
- You don't have a sunny outdoor space.
- You are looking for a low-maintenance indoor plant.
Purple Fountain Grass
Pennisetum setaceum 'Rubrum'Gardeners looking for a dramatic ornamental grass to add color and texture to their landscape.
✅ Choose This Plant If...
- You want a striking focal point in your garden.
- You need a drought-tolerant plant for a sunny location.
- You desire a plant with beautiful purple foliage and plumes.
- You want to attract birds to your garden.
- You need a deer-resistant plant.
❌ Skip This Plant If...
- You live in a cold climate and don't want to treat it as an annual.
- You don't have a sunny location.
- You are looking for a low-maintenance indoor plant.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Cockscomb needs full sun (at least 6-8 hours of direct sunlight daily), while Purple Fountain Grass prefers full sun (at least 6 hours of direct sunlight per day).
💡 Pro Tips For Comparing These Plants
Cockscomb Care Tips
Celosia is primarily an outdoor plant that requires full sun and well-draining soil. Indoor cultivation is challenging due to the high light requirements. Maintaining adequate sunlight and preventing overwatering are crucial for success. Flowering indoors is unlikely without supplemental lighting.
- Provide at least 6-8 hours of direct sunlight daily.
- Water deeply but infrequently, allowing the soil to dry slightly between waterings.
- Fertilize regularly during the growing season.
- Deadhead spent flowers to encourage more blooms.
- Protect from strong winds.
Purple Fountain Grass Care Tips
Purple Fountain Grass is primarily an outdoor plant and will struggle indoors due to its high light requirements. It needs full sun and well-draining soil. While it can be grown in containers, it requires regular watering and fertilization. Overwintering indoors is possible in colder climates, but the plant may not thrive.
- Plant in well-draining soil in a sunny location.
- Water deeply but infrequently, allowing the soil to dry out between waterings.
- Fertilize in spring with a balanced slow-release fertilizer.
- Cut back foliage in late fall or early spring.
- Protect from frost in colder climates.
⚠️ Common Problems & Solutions — Plant Care Comparison
Cockscomb
Purple Fountain Grass
❓ Frequently Asked Questions — Comparing These Plants
Cockscomb
What are the light requirements for Cockscomb?
Cockscomb needs at least 6-8 hours of direct sunlight per day to thrive and produce vibrant blooms. Indoors, place your Cockscomb near a south-facing window where it can receive ample sunlight. If natural light is insufficient, supplement with grow lights.
How do I care for Cockscomb?
Cockscomb thrives in warm, sunny conditions with well-draining soil. Water regularly, allowing the top inch of soil to dry out between waterings. Avoid overwatering, which can lead to root rot. Fertilize every 2-3 weeks during the growing season (spring and summer) with a balanced liquid fertilizer to promote abundant blooms.
How do I propagate Cockscomb?
Cockscomb is primarily propagated from seeds.
Purple Fountain Grass
What are the light requirements for Purple Fountain Grass?
Purple Fountain Grass requires at least 6-8 hours of direct sunlight per day to thrive and develop its characteristic vibrant purple foliage and abundant flower plumes. Insufficient sunlight can lead to leggy growth, faded color, and reduced flowering. When planting, choose a location that receives full sun throughout the day. If growing in containers, rotate the plant regularly to ensure even sun exposure on all sides. In hotter climates, some afternoon shade may be beneficial to prevent scorching, but avoid placing it in deep shade, which will hinder its growth. Supplemental lighting may be necessary if grown indoors during winter months.
How do I care for Purple Fountain Grass?
Purple Fountain Grass thrives in full sun and well-draining soil. Water thoroughly when the top inch of soil feels dry, but avoid overwatering, which can lead to root rot. Fertilize monthly during the growing season (spring and summer) with a balanced fertilizer to promote healthy growth and vibrant blooms. Prune away dead or damaged foliage in late winter or early spring before new growth emerges. In colder climates, treat it as an annual or bring it indoors during the winter. Provide adequate air circulation to prevent fungal diseases. Regularly inspect for pests like aphids or spider mites, and treat accordingly. Avoid planting in overly compacted or poorly draining soil. Mulching around the base can help retain moisture and suppress weeds. Protect from strong winds.
How do I propagate Purple Fountain Grass?
Purple Fountain Grass can be propagated by division. In early spring, carefully dig up the plant and divide the root ball into smaller clumps, ensuring each clump has healthy roots and foliage. Replant the divisions in well-draining soil and water thoroughly. Keep the soil consistently moist until the new plants are established. Division is the most reliable method. Seed propagation is possible but can be inconsistent in producing plants true to the ‘Rubrum’ cultivar. Stem cuttings are not typically used for propagating this grass. Keikis are not applicable as this plant doesn’t produce them. Ensure good air circulation to prevent fungal diseases after dividing.
Last updated: May 7, 2026 — Plant care data reviewed and verified by our editorial team.