Mullein vs Speedwell Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Mullein
Verbascum thapsus
Great Mullein is a biennial plant characterized by a rosette of large, velvety, gray-green leaves in its first year. In the second year, it sends up a tall, erect flower stalk that can reach up to 2 meters in height. This stalk is densely covered with small, yellow flowers that bloom sequentially from the bottom upwards. It's primarily an outdoor plant, grown for its striking architectural form and traditional medicinal uses. Indoor cultivation is extremely challenging due to its need for intense sunlight and space.
Speedwell
Veronica spp.
Speedwell encompasses a diverse genus of flowering plants, primarily herbaceous perennials, though some are annuals or shrubs. They exhibit a range of growth habits, from creeping groundcovers to upright forms. The flowers are typically small and blue, but can also be pink, white, or purple, arranged in spikes or racemes. Speedwell is primarily grown outdoors in gardens and meadows for its attractive flowers and ability to attract pollinators. While some species are relatively adaptable, they generally require specific outdoor conditions that are difficult to replicate indoors.
Quick Plant Comparison
| Feature | Mullein | Speedwell |
|---|---|---|
| Light | Full sun (at least 6-8 hours of direct sunlight daily) | Full sun to partial shade |
| Watering | Every 2-4 weeks, depending on weather and soil drainage | Every 3-7 days, depending on weather and soil drainage |
| Humidity | 30-50% | 40-60% |
| Temperature | 10-30°C | 15-24°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate To Fast | Moderate To Fast, Some Species Can Be Aggressive Spreaders |
| Max Height | 1-2 meters (outdoor) | 10-90 cm (outdoor) |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining, sandy or gravelly soil. Mullein tolerates poor soil conditions. | Well-draining, loamy soil |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 5 minutes weekly (weeding, deadheading) | 15 minutes weekly (outdoor) |
🔬 Botanical Information — Comparing These Plants
Mullein
| Scientific Name | Verbascum thapsus |
|---|---|
| Family | Scrophulariaceae |
| Native To | Europe, Asia, North Africa; naturalized in the Americas and Australia |
| Also Known As | Great Mullein, Common Mullein, Woolly Mullein, Aaron's Rod |
| Leaves | The leaves of Mullein are large, oblong to lance-shaped, and covered in dense, woolly hairs, giving them a soft, velvety texture and a gray-green color. The basal leaves can be up to 30 cm long, while the stem leaves are smaller and alternate along the flower stalk. |
| Flowers | Mullein produces numerous small, yellow flowers that are densely packed along the upper portion of the flower stalk. The flowers bloom sequentially from the bottom upwards over a long period in summer. |
Speedwell
| Scientific Name | Veronica spp. |
|---|---|
| Family | Plantaginaceae |
| Native To | Europe, Asia, North Africa, North America |
| Also Known As | Speedwell, Gypsyweed, Bird's Eye |
| Leaves | Leaves are typically small, oval or lance-shaped, and arranged oppositely or alternately along the stem. The color is usually green, but some varieties have variegated foliage. |
| Flowers | Speedwell flowers outdoors in spring and summer. The flowers are small and typically blue, but can also be pink, white, or purple. They are arranged in spikes or racemes. |
📏 Size & Growth — Plant Comparison
Mullein
Speedwell
🌱 Propagation — Comparing Plant Growth
Mullein
Methods: Seed
Difficulty: Easy
Tips: Sow seeds directly into the ground in spring or fall. Mullein seeds require light to germinate, so do not bury them deeply. Keep the soil moist until germination occurs.
Speedwell
Methods: Stem cuttings, Division, Seed
Difficulty: Easy To Moderate
Tips: For stem cuttings, take cuttings in spring or summer and root them in water or moist soil. Division is best done in spring or fall. Sow seeds in spring after the last frost.
✨ Benefits & Features — Comparing Plant Value
Mullein
Mullein's velvety leaves and tall flower stalk make it a striking addition to any garden. Its drought tolerance and ability to thrive in poor soil make it a low-maintenance choice for challenging locations.
- ✓ Attracts pollinators
- ✓ Drought-tolerant
- ✓ Unique architectural form
- ✓ Traditional medicinal uses
- ✓ Low maintenance
- ⚠️ Toxic to pets
Speedwell
Speedwell is known for its long blooming period and ability to attract pollinators. The flowers come in a variety of colors, and the plant is relatively low-maintenance. Some species spread aggressively, making them useful as groundcovers.
- ✓ Attracts pollinators
- ✓ Provides long-lasting color in the garden
- ✓ Deer-resistant
- ✓ Relatively low-maintenance
- ✓ Can be used as a groundcover
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Mullein
Speedwell
🌞 Light Requirements
Mullein
Full sun (at least 6-8 hours of direct sunlight daily)
Low light tolerant: ❌ No
Speedwell
Full sun to partial shade
Low light tolerant: ❌ No
💧 Watering Needs
Mullein
Water deeply when the soil is dry to the touch. Mullein is drought-tolerant once established. Overwatering can lead to root rot. Allow the soil to dry out completely between waterings. Signs of underwatering include wilting and drooping leaves; overwatering presents as yellowing leaves and a soggy soil.
Speedwell
Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Speedwell prefers consistently moist, but not soggy, soil. In hotter weather, more frequent watering may be necessary. Reduce watering during dormancy.
🌡️ Temperature & Humidity
Mullein
Temperature: 10-30°C
Humidity: 30-50%
Speedwell
Temperature: 15-24°C
Humidity: 40-60%
🤔 Which Plant Is Right For You?
Mullein
Verbascum thapsusGardeners looking for a striking, drought-tolerant plant for a sunny location.
✅ Choose This Plant If...
- You want a drought-tolerant plant for a sunny garden.
- You are interested in traditional medicinal herbs.
- You want to attract pollinators to your garden.
- You appreciate plants with a unique architectural form.
- You have poor soil conditions that other plants struggle in.
❌ Skip This Plant If...
- You have limited sunlight available.
- You are looking for an easy-to-grow indoor plant.
- You have pets that might ingest the plant.
Speedwell
Veronica spp.Outdoor gardeners looking for a low-maintenance, flowering groundcover or border plant that attracts pollinators.
✅ Choose This Plant If...
- You want a low-maintenance perennial for your garden.
- You want to attract pollinators to your yard.
- You need a deer-resistant plant.
- You want a long-blooming flower.
- You want a plant with a variety of colors and growth habits.
❌ Skip This Plant If...
- You are looking for an indoor plant.
- You have pets that might ingest it.
- You have limited sunlight in your garden.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Mullein needs full sun (at least 6-8 hours of direct sunlight daily), while Speedwell prefers full sun to partial shade.
Mullein has moderate to fast growth, while Speedwell grows moderate to fast, some species can be aggressive spreaders.
💡 Pro Tips For Comparing These Plants
Mullein Care Tips
Mullein is an outdoor plant that is extremely difficult to grow indoors due to its high light requirements and large size. It needs full sun and well-draining soil. Indoor cultivation is generally not recommended. It is toxic to pets if ingested.
- Provide full sun for optimal growth.
- Ensure well-draining soil to prevent root rot.
- Avoid overwatering, especially in winter.
- Deadhead spent flowers to encourage continued blooming.
- Protect young plants from frost in their first winter.
Speedwell Care Tips
Speedwell is primarily an outdoor plant and is challenging to grow indoors due to its high light requirements and need for specific temperature and humidity conditions. It requires full sun and well-draining soil. Indoor cultivation is not recommended.
- Provide well-draining soil to prevent root rot.
- Deadhead spent flowers regularly to encourage more blooms.
- Fertilize in spring with a balanced fertilizer.
- Divide plants every few years to prevent overcrowding.
- Monitor for pests and diseases and treat promptly.
⚠️ Common Problems & Solutions — Plant Care Comparison
Mullein
Speedwell
❓ Frequently Asked Questions — Comparing These Plants
Mullein
What are the light requirements for Mullein?
Mullein thrives in full sun, requiring at least six to eight hours of direct sunlight per day. Insufficient light can result in leggy growth, reduced flowering, and overall weaker plants. When planting Mullein, choose a location that receives unobstructed sunlight throughout the day. South-facing gardens or open fields are ideal. If growing Mullein indoors, place it near a sunny window or supplement with grow lights. Rotate the plant regularly to ensure even light exposure. Monitor the plant for signs of inadequate light, such as stretching towards the light source or pale foliage. Adjust the plant’s position or supplement with artificial lighting as needed to provide the necessary sunlight for healthy growth and abundant flowering.
How do I care for Mullein?
Mullein is generally easy to care for, but specific conditions will encourage optimal growth and flowering. Plant Mullein in well-draining soil, preferably sandy or gravelly, in a location that receives at least six hours of sunlight daily. Water deeply but infrequently, allowing the soil to dry out between waterings. Avoid overwatering, as this can lead to root rot. Fertilize sparingly, if at all, as Mullein thrives in nutrient-poor soil. Deadhead spent flowers to encourage additional blooming. In colder climates, provide winter protection by mulching around the base of the plant. Be mindful of self-seeding, as Mullein can spread readily. Monitor for pests and diseases, although Mullein is generally resistant. Prune back the flower stalk after blooming to maintain a tidy appearance. Ensure good air circulation to prevent fungal issues.
How do I propagate Mullein?
Mullein is most easily propagated by seed. Collect seeds from dried flower stalks in the fall. Direct sow seeds in the spring after the last frost, or start indoors 6-8 weeks before the last frost. Surface sow the seeds as they need light to germinate. Keep the soil moist but not waterlogged. Seedlings should emerge in 14-21 days. Thin seedlings to allow adequate spacing. Mullein can also be propagated by root cuttings in the spring or fall. Dig up a small section of root and replant it in well-draining soil. Keep the soil moist until new growth appears. Division of offsets is possible, but less common. Stem cuttings are not an effective method for Mullein.
Speedwell
What are the light requirements for Speedwell?
Speedwell flourishes in full sun, requiring at least six hours of direct sunlight each day for optimal growth and abundant blooming. While it can tolerate some partial shade, especially in hotter climates, insufficient light can lead to leggy growth and reduced flowering. When planting Speedwell, choose a location that receives ample sunlight throughout the day. If growing indoors, place the plant near a sunny window, ideally facing south or east. Rotate the plant regularly to ensure even light exposure on all sides. In areas with intense afternoon sun, providing some light shade during the hottest part of the day can prevent leaf scorch.
How do I care for Speedwell?
Speedwell thrives in well-draining soil and requires regular watering, especially during dry periods. Aim to keep the soil consistently moist, but avoid overwatering, which can lead to root rot. Provide Speedwell with at least six hours of sunlight daily for optimal blooming. In hotter climates, some afternoon shade can be beneficial. Fertilize your Speedwell every 4-6 weeks during the growing season with a balanced fertilizer to promote healthy growth and abundant blooms. Deadhead spent flowers regularly to encourage continuous flowering. Prune back the plant in late fall or early spring to maintain its shape and promote bushier growth. Protect Speedwell from extreme cold and frost in colder climates. Monitor for pests and diseases, and treat promptly if necessary.
How do I propagate Speedwell?
Speedwell can be propagated through division, stem cuttings, and seeds.
Last updated: May 1, 2026 — Plant care data reviewed and verified by our editorial team.