Lyme Grass vs Speedwell Plant Comparison

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

Lyme Grass

Lyme Grass

Leymus arenarius

VS
Speedwell

Speedwell

Veronica spp.

Lyme Grass

Lyme Grass

Leymus arenarius

Lyme grass (Leymus arenarius) is a cool-season perennial grass known for its striking blue-gray foliage. It typically grows in clumps, reaching heights of 1 to 3 feet. This grass is native to sandy coastal areas and is well-adapted to harsh conditions like salt spray and nutrient-poor soils. It spreads aggressively via rhizomes, forming dense colonies. While primarily an outdoor plant used for erosion control and ornamental purposes, some gardeners attempt to grow it in containers. Its aesthetic appeal lies in its unique color and texture, making it a popular choice for landscaping.

Poaceae Europe, particularly coastal regions
✨ Features: Erosion control, drought tolerance, striking blue-gray foliage
📖 Read Complete Lyme Grass Guide
Speedwell

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.

Plantaginaceae Europe, Asia, North Africa, North America
✨ Features: Attracts pollinators (bees, butterflies), deer-resistant (in some cases), long blooming period.
📖 Read Complete Speedwell Guide

Quick Plant Comparison

Feature Lyme Grass Speedwell
Light Full sun Full sun to partial shade
Watering Every 1-2 weeks, depending on weather and soil drainage Every 3-7 days, depending on weather and soil drainage
Humidity 30-50% 40-60%
Temperature 10-24°C 15-24°C
Care Level Expert Expert
Growth Rate Fast Moderate To Fast, Some Species Can Be Aggressive Spreaders
Max Height 0.3-0.9 meters (1-3 feet) 10-90 cm (outdoor)
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil Well-draining sandy or loamy soil Well-draining, loamy soil
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 10 minutes weekly (mostly weeding and occasional trimming) 15 minutes weekly (outdoor)

🔬 Botanical Information — Comparing These Plants

Lyme Grass

Scientific Name Leymus arenarius
Family Poaceae
Native To Europe, particularly coastal regions
Also Known As Lyme Grass, Blue Lyme Grass, Sand Lyme Grass
Leaves The leaves are linear, stiff, and blue-gray in color. They are typically 1-2 cm wide and 20-60 cm long. The texture is somewhat rough.
Flowers It rarely flowers indoors. Outdoors, it produces inconspicuous flower spikes 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

Lyme Grass

Height 0.3-0.9 meters (1-3 feet)
Spread Spreads aggressively via rhizomes, potentially covering several feet
Growth Rate Fast
Growth Pattern Spreading, rhizomatous, clump-forming grass. It forms dense colonies and can quickly fill in an area.

Speedwell

Height 10-90 cm (outdoor)
Spread 15-60 cm (outdoor), spreads via rhizomes in some species
Growth Rate Moderate To Fast, Some Species Can Be Aggressive Spreaders
Growth Pattern Varies depending on the species. Some are creeping groundcovers, while others are upright and bushy. Some species spread via rhizomes, forming dense mats.

🌱 Propagation — Comparing Plant Growth

Lyme Grass

Methods: Division, Seed, Rhizome cuttings

Difficulty: Easy

Tips: Divide clumps in spring or fall. For seed propagation, sow seeds in spring after a cold stratification period. Rhizome cuttings can be taken and planted directly into the soil.

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

Lyme Grass

Its striking blue-gray foliage and aggressive rhizomatous growth distinguish it from other ornamental grasses. It is highly tolerant of coastal conditions, including salt spray and sandy soils.

  • ✓ Erosion control on slopes and dunes.
  • ✓ Drought tolerance reduces water usage.
  • ✓ Unique blue-gray foliage adds visual interest.
  • ✓ Low maintenance once established.
  • ✓ Provides habitat for beneficial insects.
  • 🐾 Pet Safe

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

Lyme Grass

Repotting Repotting is rarely done as it is an outdoor plant. If container grown, repot annually in spring to control rhizome spread.
Pruning Cut back dead foliage in late winter or early spring.
Fertilizing Balanced slow-release fertilizer in spring. Avoid over-fertilizing.
Seasonal Care In winter, cut back dead foliage. In spring, apply a slow-release fertilizer. Summer may require more frequent watering during dry spells. Fall is a good time for division.

Speedwell

Repotting Not applicable for indoor growing, but if grown in containers outdoors, repot every 2-3 years or as needed.
Pruning Deadhead spent flowers to encourage continued blooming. Prune back in late fall or early spring to maintain shape and size.
Fertilizing Balanced fertilizer (10-10-10) diluted to half strength, applied in spring and early summer
Seasonal Care In spring, fertilize and prune back dead growth. In summer, water regularly and deadhead spent flowers. In fall, divide plants if needed. In winter, provide mulch for protection in colder climates.

🌞 Light Requirements

Lyme Grass

Full sun

Low light tolerant: ❌ No

Speedwell

Full sun to partial shade

Low light tolerant: ❌ No

💧 Watering Needs

Lyme Grass

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, as this can lead to root rot. Established plants are drought-tolerant. Signs of underwatering include drooping or browning leaves. Overwatering can cause 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

Lyme Grass

Temperature: 10-24°C

Humidity: 30-50%

Speedwell

Temperature: 15-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Lyme Grass

Lyme Grass

Leymus arenarius
Care: Expert Time: 10 minutes weekly (mostly weeding and occasional trimming) Beginner: No

Gardeners looking for a low-maintenance, drought-tolerant ornamental grass for coastal or sandy areas.

✅ Choose This Plant If...

  • You want a drought-tolerant ornamental grass for a sunny location.
  • You need a plant for erosion control in sandy soils.
  • You appreciate the unique blue-gray foliage color.
  • You want a low-maintenance plant once established.
  • You live in a coastal area with salt spray.

❌ Skip This Plant If...

  • You have limited space, as it spreads aggressively.
  • You cannot provide full sun.
  • You are looking for a low-maintenance indoor plant.
📍 Ideal Location: Outdoor garden, coastal area, sandy soil
🎨 Style: Coastal, Natural, Modern
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, grasses are generally non-toxic to dogs, cats, and horses. However, ingestion of large quantities may cause mild gastrointestinal upset.
Speedwell

Speedwell

Veronica spp.
Care: Expert Time: 15 minutes weekly (outdoor) Beginner: No

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.
📍 Ideal Location: Outdoor garden bed or border with full sun exposure.
🎨 Style: Cottage, Naturalistic, Meadow
🏠 Apartment Friendly: No
⚠️ Some species of Veronica contain glycosides that can cause mild gastrointestinal upset in dogs, cats, and horses if ingested. Symptoms may include vomiting, diarrhea, and loss of appetite. All parts of the plant are potentially toxic.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Lyme Grass ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

☀️

Lyme Grass needs full sun, while Speedwell prefers full sun to partial shade.

📈

Lyme Grass has fast growth, while Speedwell grows moderate to fast, some species can be aggressive spreaders.

💡 Pro Tips For Comparing These Plants

Lyme Grass Care Tips

Lyme grass is primarily an outdoor plant that thrives in full sun and well-draining soil. Indoor cultivation is challenging due to its high light requirements and aggressive spreading habit. It needs excellent drainage to prevent root rot. Regular division is necessary to control its spread.

  • Plant in well-draining soil to prevent root rot.
  • Provide full sun for optimal color and growth.
  • Divide clumps every few years to control spread.
  • Water deeply but infrequently once established.
  • Cut back dead foliage in late winter or early spring.
❄️ Winter: Cut back dead foliage in late winter or early spring. Ensure good drainage to prevent root rot.
☀️ Summer: Water more frequently during dry spells. Provide full sun for optimal growth and color.

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.
❄️ Winter: In colder climates, provide mulch around the base of the plant to protect the roots from freezing. Reduce watering during dormancy. Prune back dead growth in late fall or early spring.
☀️ Summer: Water regularly during hot weather. Deadhead spent flowers to encourage continued blooming. Monitor for pests and diseases.

⚠️ Common Problems & Solutions — Plant Care Comparison

Lyme Grass

Common Issues: Root rot, Rust, Aphids, Spreading too aggressively
Solutions: Ensure well-draining soil and avoid overwatering. Treat rust with a fungicide. Control aphids with insecticidal soap. Contain spread by using barriers or planting in containers.

Speedwell

Common Issues: Powdery mildew, Root rot, Aphids
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Root rot: Ensure well-draining soil and avoid overwatering. Aphids: Spray with insecticidal soap.

❓ Frequently Asked Questions — Comparing These Plants

Lyme Grass

What are the light requirements for Lyme Grass?

Lyme Grass requires ample sunlight to thrive. Aim for at least six hours of direct sunlight daily, especially for aquatic varieties. If grown indoors in a large container, position the plant near a south-facing window or supplement with artificial grow lights. Insufficient light can lead to leggy growth, pale foliage, and reduced vigor. When planting in a pond, consider the angle of the sun and choose a location where the grass will receive maximum sunlight exposure throughout the day. Partial shade is tolerated, particularly in hotter climates, but full sun yields the best results for vibrant color and robust growth. Monitoring light levels and adjusting the plant’s position accordingly is crucial for its health.

How do I care for Lyme Grass?

Lyme Grass thrives in full sun to partial shade, requiring at least 6 hours of direct sunlight for optimal growth. Water quality is paramount; use dechlorinated water or allow tap water to sit for 24 hours to dissipate chlorine. Maintain a water pH between 6.0 and 7.5. For aquatic Lyme Grass, ensure the crown of the plant is just above the water level. For semi-aquatic Lyme Grass, keep the soil consistently moist. Fertilize sparingly with a diluted aquatic plant fertilizer during the growing season (spring and summer). Avoid over-fertilizing, as this can lead to algae blooms. Prune away any dead or yellowing foliage to maintain its appearance and prevent disease. Regularly check for pests like aphids and treat accordingly.

How do I propagate Lyme Grass?

Lyme Grass is easily propagated through division or cuttings.

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: April 24, 2026 — Plant care data reviewed and verified by our editorial team.