Black-Eyed Susan vs Thyme Plant Comparison

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

Black-Eyed Susan

Black-Eyed Susan

Rudbeckia hirta

VS
Thyme

Thyme

Thymus vulgaris

Black-Eyed Susan

Black-Eyed Susan

Rudbeckia hirta

Rudbeckia hirta, commonly known as Black-Eyed Susan, is a flowering plant typically grown as an annual or short-lived perennial. It features daisy-like flowers with bright yellow petals surrounding a dark brown or black central cone. The plant grows upright, reaching heights of 1 to 3 feet. It is primarily an outdoor plant, valued for its vibrant blooms and ability to attract pollinators to gardens. While technically possible to grow indoors, it requires very specific and intense lighting conditions to thrive and bloom, making it challenging.

Asteraceae Eastern and Central North America
✨ Features: Attracts butterflies and bees, deer resistant, long blooming period.
📖 Read Complete Black-Eyed Susan Guide
Thyme

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.

Lamiaceae Mediterranean region
✨ Features: Aromatic foliage, culinary uses, drought tolerance
📖 Read Complete Thyme Guide

Quick Plant Comparison

Feature Black-Eyed Susan Thyme
Light Full sun (at least 6-8 hours of direct sunlight daily) Full sun (at least 6-8 hours of direct sunlight daily)
Watering Outdoors: Every 3-7 days depending on weather. Indoors (not recommended): Possibly more frequent, but monitor soil moisture carefully. Every 1-2 weeks, depending on environmental conditions and pot size. Allow soil to dry between waterings.
Humidity 30-50% 40-60%
Temperature 18-27°C 15-24°C
Care Level Expert Expert
Growth Rate Moderate Moderate
Max Height Outdoors: 30-90 cm. Indoors (unlikely): Significantly smaller, if it survives. 15-30 cm (indoors, often smaller)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining soil, such as a mix of potting soil, perlite, and sand. Well-draining, sandy loam soil
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 5-10 minutes weekly (deadheading) 10 minutes weekly

🔬 Botanical Information — Comparing These Plants

Black-Eyed Susan

Scientific Name Rudbeckia hirta
Family Asteraceae
Native To Eastern and Central North America
Also Known As Black-Eyed Susan, Brown-Eyed Susan, Gloriosa Daisy
Leaves The leaves are lance-shaped, rough in texture, and medium green in color. They are typically 2-6 inches long and arranged alternately along the stem.
Flowers Flowers are daisy-like with bright yellow petals surrounding a dark brown or black central cone. They bloom profusely throughout the summer and into the fall.

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

Black-Eyed Susan

Height Outdoors: 30-90 cm. Indoors (unlikely): Significantly smaller, if it survives.
Spread 30-60 cm
Growth Rate Moderate
Growth Pattern Upright, bushy growth habit. It forms clumps that can spread over time, but it is not considered aggressively invasive.

Thyme

Height 15-30 cm (indoors, often smaller)
Spread 20-45 cm
Growth Rate Moderate
Growth Pattern Thyme grows as a low-spreading, woody-based perennial. It forms a dense mat of stems and leaves, with a tendency to become leggy if not pruned regularly. It spreads outwards, but is not considered highly aggressive.

🌱 Propagation — Comparing Plant Growth

Black-Eyed Susan

Methods: Seed, Division

Difficulty: Easy

Tips: For seeds, sow directly into the garden in spring or start indoors 6-8 weeks before the last frost. For division, divide clumps in early spring or fall.

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

Black-Eyed Susan

The dark central cone provides a striking contrast to the bright yellow petals. It's a popular choice for attracting pollinators and is relatively deer-resistant.

  • ✓ Attracts pollinators
  • ✓ Adds vibrant color to gardens
  • ✓ Deer resistant
  • ✓ Relatively low maintenance outdoors
  • ✓ Native plant supports local ecosystems
  • ⚠️ Toxic to pets

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

Black-Eyed Susan

Repotting Not typically needed as it's often grown as an annual. If grown as a perennial, repot every 2-3 years in spring.
Pruning Deadhead spent flowers regularly to encourage more blooms. Cut back foliage in late fall after it dies back.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 4-6 weeks during the growing season (spring and summer).
Seasonal Care Deadhead spent flowers to encourage continued blooming. In colder climates, treat as an annual or provide winter protection.

Thyme

Repotting Repot every 1-2 years in spring, or when the plant becomes root-bound.
Pruning Prune regularly to maintain shape and encourage bushier growth. Prune after flowering to prevent legginess.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, applied sparingly in spring and summer.
Seasonal Care In winter, reduce watering and provide protection from frost if grown outdoors. In summer, ensure adequate sunlight and water regularly.

🌞 Light Requirements

Black-Eyed Susan

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

Low light tolerant: ❌ No

Thyme

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

Low light tolerant: ❌ No

💧 Watering Needs

Black-Eyed Susan

Water thoroughly when the top inch of soil feels dry to the touch. Avoid overwatering, which can lead to root rot. Allow excess water to drain away. Signs of underwatering include wilting leaves; overwatering includes yellowing leaves and soggy soil.

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

Black-Eyed Susan

Temperature: 18-27°C

Humidity: 30-50%

Thyme

Temperature: 15-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Black-Eyed Susan

Black-Eyed Susan

Rudbeckia hirta
Care: Expert Time: 5-10 minutes weekly (deadheading) Beginner: No

Gardeners looking to add vibrant color and attract pollinators to their outdoor spaces.

✅ Choose This Plant If...

  • You want to attract pollinators to your garden.
  • You desire a long-blooming, cheerful flower.
  • You need a deer-resistant plant.
  • You want a low-maintenance outdoor plant once established.
  • You want a native North American wildflower.

❌ Skip This Plant If...

  • You have limited sunlight indoors.
  • You have pets that might ingest the plant.
  • You are looking for a low-maintenance INDOOR plant.
📍 Ideal Location: Outdoor garden, sunny border, meadow garden
🎨 Style: Cottage, Rustic, Wildflower
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Rudbeckia hirta contains glycosides that can be toxic to dogs, cats, and horses. Symptoms include dermatitis and gastrointestinal upset (vomiting, diarrhea). All parts of the plant are considered toxic.
Thyme

Thyme

Thymus vulgaris
Care: Expert Time: 10 minutes weekly Beginner: No

Experienced 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
📍 Ideal Location: Sunny windowsill or balcony (if indoors), outdoor herb garden
🎨 Style: Mediterranean, Cottage, Rustic
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Thyme contains essential oils that can be toxic to dogs, cats, and horses. Symptoms include vomiting, diarrhea, and central nervous system depression. All parts of the plant are potentially toxic.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Neither - caution
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

Black-Eyed Susan Care Tips

Black-Eyed Susans are primarily outdoor plants that require full sun and well-draining soil. Growing them indoors is extremely challenging due to their high light requirements. They are toxic to pets. Indoor survival is unlikely without specialized grow lights and careful monitoring.

  • Provide full sun for optimal blooming.
  • Ensure well-draining soil to prevent root rot.
  • Deadhead spent flowers regularly.
  • Water deeply but infrequently.
  • Monitor for pests and diseases.
❄️ Winter: In colder climates, cut back foliage after it dies back. Mulch around the base of the plant to provide winter protection. Consider treating as an annual in very cold regions.
☀️ Summer: Water regularly during dry spells. Deadhead spent flowers to encourage continued blooming. Monitor for pests and diseases.

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.
❄️ Winter: Reduce watering during the winter months. If grown outdoors, provide protection from frost and snow. If grown indoors, ensure adequate light and ventilation.
☀️ Summer: Water regularly during the summer months, especially during hot weather. Provide adequate sunlight and ensure good air circulation. Prune after flowering to encourage bushier growth.

⚠️ Common Problems & Solutions — Plant Care Comparison

Black-Eyed Susan

Common Issues: Powdery mildew, fungal leaf spot, aphids, spider mites
Solutions: Powdery mildew/leaf spot: Improve air circulation, use a fungicide. Aphids/spider mites: Insecticidal soap or neem oil.

Thyme

Common Issues: Root rot, Spider mites, Powdery mildew, Leggy growth
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Spider mites: Treat with insecticidal soap or neem oil. Powdery mildew: Improve air circulation and apply a fungicide. Leggy growth: Prune regularly to encourage bushier growth and provide adequate light.

❓ Frequently Asked Questions — Comparing These Plants

Black-Eyed Susan

What are the light requirements for Black-Eyed Susan?

Black-Eyed Susans are sun-loving plants and require at least 6 hours of direct sunlight each day to thrive. Insufficient light can lead to leggy growth, reduced blooming, and pale foliage. When grown indoors, place them near a south-facing window where they can receive ample sunlight. If natural light is limited, supplement with grow lights to ensure they get the light they need.

How do I care for Black-Eyed Susan?

Black-Eyed Susans thrive in full sun, requiring at least 6 hours of direct sunlight daily. Well-draining soil is crucial to prevent root rot; amend heavy clay soils with compost or sand. Water regularly, especially during dry periods, but avoid overwatering. Fertilize sparingly with a balanced fertilizer in the spring to encourage blooming. Deadhead spent flowers to promote continuous blooming throughout the season.

How do I propagate Black-Eyed Susan?

Black-Eyed Susans can be propagated through division or seeds.

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.