Rainbow Fern vs Thyme Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Rainbow Fern
Selaginella uncinata
Selaginella uncinata, commonly known as Rainbow Fern, is a creeping, mat-forming plant prized for its iridescent blue-green foliage. The shimmering effect is caused by the reflection of light off the leaf surfaces. It is not a true fern, but a spikemoss. While it can be grown indoors, it requires very high humidity and consistent moisture, making it a challenging houseplant. People grow it for its unique coloration and texture, adding a touch of the exotic to terrariums or humid environments.
Thyme
Thymus vulgaris
Thymus vulgaris, commonly known as common thyme, is a low-growing, woody-based perennial herb. It typically reaches a height of 15-30 cm (6-12 inches). The plant features small, grayish-green leaves and produces clusters of tiny, lilac or pink flowers in the summer. While primarily an outdoor plant, thyme is often grown indoors for culinary and ornamental purposes. People grow it for its aromatic leaves, which are widely used as a culinary herb, and for its attractive appearance in herb gardens and containers. It is not naturally an indoor plant and requires very specific conditions to thrive indoors.
Quick Plant Comparison
| Feature | Rainbow Fern | Thyme |
|---|---|---|
| Light | Bright, indirect light. Avoid direct sunlight, which can scorch the delicate fronds. | Full sun (at least 6-8 hours of direct sunlight daily) |
| Watering | Every 2-3 days, depending on humidity and temperature | Every 1-2 weeks, depending on environmental conditions and pot size. Allow soil to dry between waterings. |
| Humidity | 70-90% | 40-60% |
| Temperature | 18-24°C | 15-24°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | 15-30 cm | 15-30 cm (indoors, often smaller) |
| Pet Safety | ✅ Safe | ❌ Toxic To Pets |
| Soil | Well-draining, moisture-retentive mix such as peat moss, perlite, and vermiculite. | Well-draining, sandy loam soil |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 15-20 minutes weekly | 10 minutes weekly |
🔬 Botanical Information — Comparing These Plants
Rainbow Fern
| Scientific Name | Selaginella uncinata |
|---|---|
| Family | Selaginellaceae |
| Native To | China |
| Also Known As | Rainbow Fern, Peacock Fern, Blue Fern, Spikemoss |
| Leaves | Small, scale-like leaves arranged in overlapping rows along the stems. The leaves are typically a vibrant blue-green color with an iridescent sheen. They are delicate and finely textured. |
| Flowers | Selaginella uncinata does not produce flowers in the typical sense. It reproduces via spores, which are produced in strobili (cone-like structures) at the tips of the stems. These are rarely seen indoors. |
Thyme
| Scientific Name | Thymus vulgaris |
|---|---|
| Family | Lamiaceae |
| Native To | Mediterranean region |
| Also Known As | Common Thyme, Garden Thyme |
| Leaves | The leaves of thyme are small, oval-shaped, and grayish-green in color. They are typically about 4-10 mm long and have a slightly fuzzy texture. The leaves are highly aromatic, releasing their scent when crushed. |
| Flowers | Thyme produces small, tubular flowers in clusters during the summer. The flowers are typically lilac or pink in color, but can also be white. Indoors, flowering is rare unless provided with optimal conditions. |
📏 Size & Growth — Plant Comparison
Rainbow Fern
Thyme
🌱 Propagation — Comparing Plant Growth
Rainbow Fern
Methods: Division, Stem cuttings
Difficulty: Moderate
Tips: Divide the plant at the roots or take stem cuttings and place them in a humid environment until they root. A propagation box or terrarium works well.
Thyme
Methods: Stem cuttings, Seed, Division
Difficulty: Easy
Tips: Take stem cuttings in spring or summer and root them in well-draining soil. Division can be done in spring or fall.
✨ Benefits & Features — Comparing Plant Value
Rainbow Fern
The Rainbow Fern's iridescent blue-green foliage sets it apart from other ferns and houseplants. This shimmering effect is a result of structural coloration, where light interacts with the leaf's surface. It is not a true fern, but a spikemoss, belonging to the genus Selaginella.
- ✓ Adds a unique visual element to indoor spaces
- ✓ Creates a calming and relaxing atmosphere
- ✓ Can be used in terrariums and vivariums
- ✓ Non-toxic to pets
- ✓ Offers a connection to nature indoors
- 🐾 Pet Safe
Thyme
Thyme is known for its strong aromatic scent and culinary uses. It is also drought-tolerant and attracts pollinators. Its small leaves and low-growing habit make it a good ground cover option.
- ✓ Provides fresh herbs for cooking
- ✓ Adds aromatic fragrance to the garden
- ✓ Attracts pollinators
- ✓ Drought-tolerant and low-maintenance (outdoors)
- ✓ Can be used for medicinal purposes
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Rainbow Fern
Thyme
🌞 Light Requirements
Rainbow Fern
Bright, indirect light. Avoid direct sunlight, which can scorch the delicate fronds.
Low light tolerant: ❌ No
Thyme
Full sun (at least 6-8 hours of direct sunlight daily)
Low light tolerant: ❌ No
💧 Watering Needs
Rainbow Fern
Keep the soil consistently moist but not soggy. Water when the top of the soil feels slightly dry to the touch. Overwatering can lead to root rot, while underwatering will cause the fronds to dry out and turn brown. Use distilled or rainwater to avoid mineral buildup.
Thyme
Water thoroughly when the top inch of soil is dry. Overwatering can lead to root rot, so ensure good drainage. Underwatering will cause the leaves to dry out and become brittle. Check the soil moisture regularly, especially during hot weather.
🌡️ Temperature & Humidity
Rainbow Fern
Temperature: 18-24°C
Humidity: 70-90%
Thyme
Temperature: 15-24°C
Humidity: 40-60%
🤔 Which Plant Is Right For You?
Rainbow Fern
Selaginella uncinataExperienced plant enthusiasts who can provide a humid environment like a terrarium.
✅ Choose This Plant If...
- You want a unique and visually striking plant with iridescent foliage.
- You can provide a consistently humid environment, such as a terrarium.
- You enjoy the challenge of caring for demanding plants.
- You want to add a touch of the exotic to your indoor garden.
- You appreciate the delicate beauty of ferns and mosses.
❌ Skip This Plant If...
- You struggle to maintain consistent watering schedules.
- You live in a dry climate and cannot provide high humidity.
- You are a beginner plant owner looking for low-maintenance options.
Thyme
Thymus vulgarisExperienced gardeners who can provide the specific conditions thyme needs to thrive indoors or those with outdoor gardens.
✅ Choose This Plant If...
- You have a sunny outdoor garden or balcony
- You enjoy cooking with fresh herbs
- You want a drought-tolerant plant
- You are experienced with growing herbs
- You appreciate aromatic plants
❌ Skip This Plant If...
- You have limited sunlight indoors
- You tend to overwater plants
- You have pets that might ingest the plant
- You are a beginner gardener
- You don't have time for regular pruning
🎯 Quick Verdict
⚡ 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
Rainbow Fern Care Tips
Rainbow Ferns are challenging houseplants due to their high humidity and moisture requirements. They thrive in terrariums or enclosed environments where humidity can be maintained. Consistent watering and bright, indirect light are crucial for their survival indoors. It is primarily an outdoor plant in tropical climates.
- Use distilled or rainwater to avoid mineral buildup on the fronds.
- Maintain high humidity by misting regularly or using a humidifier.
- Provide bright, indirect light to enhance the iridescent coloration.
- Ensure good drainage to prevent root rot.
- Monitor for pests and treat promptly.
Thyme Care Tips
Thyme is primarily an outdoor plant and requires full sun and well-draining soil. Growing it indoors is challenging due to its high light requirements. It is prone to root rot if overwatered. Requires very bright light and careful watering to survive indoors.
- Provide at least 6 hours of direct sunlight daily.
- Use well-draining soil to prevent root rot.
- Prune regularly to encourage bushier growth.
- Avoid overwatering; allow the soil to dry out between waterings.
- Fertilize sparingly with a balanced liquid fertilizer.
⚠️ Common Problems & Solutions — Plant Care Comparison
Rainbow Fern
Thyme
❓ Frequently Asked Questions — Comparing These Plants
Rainbow Fern
What are the light requirements for Rainbow Fern?
Rainbow Fern requires bright, indirect light to maintain its vibrant coloration. Direct sunlight can scorch its delicate fronds, so avoid placing it in direct sun exposure. An east-facing window is often ideal, providing gentle morning light. A north-facing window can also work, but supplemental lighting might be necessary if the plant doesn’t receive enough natural light. If placed near a south or west-facing window, use a sheer curtain to filter the light. Insufficient light can cause the colors to fade and the plant to become leggy. Observe the plant’s response to light and adjust its placement accordingly.
How do I care for Rainbow Fern?
Rainbow Fern thrives in bright, indirect light and consistently moist soil. Water thoroughly when the top inch of soil feels slightly dry, using distilled or filtered water to avoid mineral buildup. Maintain high humidity levels, ideally above 70%, through regular misting, a humidifier, or a pebble tray. Plant in a well-draining, acidic potting mix. Fertilize lightly during the growing season (spring and summer) with a diluted liquid fertilizer. Avoid direct sunlight, which can scorch the delicate foliage. Maintain temperatures between 60-75°F (15-24°C). Prune any dead or damaged fronds to encourage new growth. Ensure good air circulation to prevent fungal diseases. Repot only when necessary, usually every 1-2 years, using a slightly larger pot.
How do I propagate Rainbow Fern?
Rainbow Fern can be propagated by division or spores.
Thyme
What are the light requirements for Thyme?
Thyme demands ample sunlight to thrive. Ideally, provide at least 6-8 hours of direct sunlight each day. Insufficient light can lead to leggy growth and reduced flowering. In indoor settings, place thyme near a south-facing window where it can receive maximum sunlight. If natural light is limited, supplement with a grow light to ensure adequate illumination.
How do I care for Thyme?
Thyme thrives in well-draining soil and requires full sun, at least 6-8 hours daily. Water thoroughly when the top inch of soil feels dry, but avoid overwatering to prevent root rot. Fertilize sparingly with a balanced liquid fertilizer during the growing season (spring and summer) to encourage blooming. Prune regularly after flowering to maintain shape and promote bushier growth.
How do I propagate Thyme?
Thyme can be easily propagated through division, stem cuttings, and layering. For division, carefully dig up an established plant in spring or fall and separate the root ball into smaller clumps. Replant each clump in well-draining soil.
Last updated: April 21, 2026 — Plant care data reviewed and verified by our editorial team.