Cotton Lavender vs Purple Fountain Grass Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Cotton Lavender
Santolina chamaecyparissus
Santolina chamaecyparissus, commonly known as Cotton Lavender, is a small, evergreen shrub prized for its aromatic, silvery-gray foliage. It typically grows to a height of 1-2 feet. The plant features finely divided leaves that give it a soft, cotton-like appearance. While it produces button-like yellow flowers in summer, it is primarily grown for its foliage. It is naturally an outdoor plant, often used in herb gardens, rock gardens, and as edging along pathways. People grow it for its ornamental value, drought tolerance, and ability to repel insects.
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 | Cotton Lavender | Purple Fountain Grass |
|---|---|---|
| Light | Full sun (at least 6 hours of direct sunlight daily) | Full sun (at least 6 hours of direct sunlight per day) |
| Watering | Every 1-2 weeks, depending on weather and soil drainage | Every 7-10 days, depending on weather and soil drainage |
| Humidity | 30-50% | 20-50% |
| Temperature | 15-25°C | 18-30°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | 0.3-0.6 meters (indoors unlikely to reach full outdoor size) | Outdoor: 0.6-1.5 meters. Indoor (unlikely to thrive): 0.3-0.6 meters |
| Pet Safety | ❌ Toxic To Pets | ✅ Safe |
| Soil | Well-draining, sandy or loamy soil | Well-draining soil, such as a sandy loam or a potting mix amended with perlite |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 15 minutes weekly (mostly pruning and checking for pests) | 15 minutes weekly |
🔬 Botanical Information — Comparing These Plants
Cotton Lavender
| Scientific Name | Santolina chamaecyparissus |
|---|---|
| Family | Asteraceae |
| Native To | Mediterranean region |
| Also Known As | Cotton Lavender, Lavender Cotton, Gray Santolina |
| Leaves | The leaves are finely divided, linear, and silvery-gray in color. They have a soft, cotton-like texture and are highly aromatic. |
| Flowers | It produces button-like yellow flowers in summer. Flowering is less common when grown indoors due to insufficient light. |
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
Cotton Lavender
Purple Fountain Grass
🌱 Propagation — Comparing Plant Growth
Cotton Lavender
Methods: Stem cuttings, Seed
Difficulty: Easy
Tips: Take stem cuttings in spring or summer. Remove the lower leaves and plant in well-draining soil. Keep the soil moist until roots develop. Seeds can be sown in spring after the last frost.
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
Cotton Lavender
Its silvery-gray foliage and strong aromatic scent distinguish it from other herbs. It is also known for its drought tolerance and insect-repelling properties.
- ✓ Drought tolerance
- ✓ Insect repellent
- ✓ Aromatic foliage
- ✓ Ornamental value
- ✓ Low maintenance (once established)
- ⚠️ 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
Cotton Lavender
Purple Fountain Grass
🌞 Light Requirements
Cotton Lavender
Full sun (at least 6 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
Cotton Lavender
Water thoroughly when the top inch of soil is dry. Avoid overwatering, as this can lead to root rot. Signs of overwatering include yellowing leaves and a soggy soil surface. Underwatering is indicated by wilting and dry, crispy leaves.
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
Cotton Lavender
Temperature: 15-25°C
Humidity: 30-50%
Purple Fountain Grass
Temperature: 18-30°C
Humidity: 20-50%
🤔 Which Plant Is Right For You?
Cotton Lavender
Santolina chamaecyparissusExperienced gardeners looking for a drought-tolerant, aromatic plant for outdoor gardens.
✅ Choose This Plant If...
- You want a drought-tolerant plant for a sunny garden
- You appreciate aromatic foliage that repels insects
- You are looking for a low-maintenance ground cover
- You want to add a silvery-gray hue to your landscape
- You enjoy using herbs in crafts and potpourri.
❌ Skip This Plant If...
- You have pets that might ingest it
- You lack a sunny outdoor space
- You are prone to overwatering plants
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
Cotton Lavender needs full sun (at least 6 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
Cotton Lavender Care Tips
Cotton Lavender is primarily an outdoor plant and will struggle indoors due to its high light requirements. It needs full sun and well-draining soil. Indoor cultivation is challenging and requires careful attention to light, watering, and ventilation. It is prone to root rot if overwatered.
- Provide at least 6 hours of direct sunlight daily
- Ensure well-draining soil to prevent root rot
- Prune regularly to maintain shape and encourage bushier growth
- Avoid overwatering, especially during the winter months
- Monitor for pests and diseases, and treat promptly.
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
Cotton Lavender
Purple Fountain Grass
❓ Frequently Asked Questions — Comparing These Plants
Cotton Lavender
What are the light requirements for Cotton Lavender?
Cotton Lavender requires at least six hours of direct sunlight per day to thrive and produce abundant blooms. Insufficient light can lead to leggy growth and reduced flowering. In indoor settings, place your Cotton Lavender near a south-facing window to maximize sunlight exposure. If natural light is limited, supplement with grow lights to provide the necessary intensity. Rotate the plant regularly to ensure even light distribution and prevent leaning towards the light source. During the summer months, be mindful of intense afternoon sun, which can scorch the foliage, and provide some light shade if necessary.
How do I care for Cotton Lavender?
Cotton Lavender thrives in full sun and well-draining soil. Water sparingly, allowing the soil to dry out completely between waterings to prevent root rot. Fertilize lightly in the spring with a balanced fertilizer to encourage blooming. Prune regularly to maintain shape and promote bushier growth, ideally after flowering. Deadhead spent blooms to encourage further flowering. Protect from excessive winter moisture, especially in colder climates. Provide good air circulation to prevent fungal diseases. Repot only when necessary, typically every 2-3 years, into a slightly larger pot with well-draining soil. Monitor for pests such as aphids and treat as needed with insecticidal soap.
How do I propagate Cotton Lavender?
Cotton Lavender can be propagated through stem cuttings. Take 4-6 inch cuttings from healthy stems, removing the lower leaves. Dip the cut end in rooting hormone and plant in well-draining potting mix. Keep the soil moist but not soggy. Rooting typically occurs within a few weeks. Division can also be done in the spring by carefully separating the root ball into smaller clumps. Replant each clump in its own pot. Cotton Lavender does not produce keiki.
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: April 18, 2026 — Plant care data reviewed and verified by our editorial team.