Myrtle Spurge vs Penstemon Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Myrtle Spurge
Euphorbia myrsinites
Myrtle Spurge is a succulent, low-growing perennial characterized by its sprawling habit and blue-gray, spirally arranged leaves. It typically reaches a height of 6-12 inches and spreads up to 24 inches wide. It is primarily grown as an ornamental ground cover in rock gardens or dry landscapes. It produces small, inconspicuous yellowish-green flowers in spring, followed by seed capsules. This plant is naturally an outdoor plant and struggles indoors due to its high light requirements and need for well-draining soil.
Penstemon
Penstemon spp.
Penstemon is a diverse genus of flowering plants, primarily herbaceous perennials, known for their vibrant, tubular flowers. They range in size from a few inches to several feet tall, with varying growth habits from upright to spreading. The flowers come in a wide array of colors, including shades of blue, purple, pink, red, and white, attracting pollinators like bees and hummingbirds. Penstemons are primarily grown outdoors in gardens and naturalized areas for their showy blooms, drought tolerance, and ability to attract wildlife. They are not typically grown indoors due to their high light requirements and need for specific environmental conditions.
Quick Plant Comparison
| Feature | Myrtle Spurge | Penstemon |
|---|---|---|
| Light | Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth. | Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal flowering. |
| Watering | Every 2-4 weeks, depending on weather and soil drainage. | Every 1-2 weeks, depending on weather and soil drainage. |
| Humidity | 20-40% | 30-50% |
| Temperature | 15-25°C | 15-27°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | 6-12 inches (outdoor) | 0.3-1.2 meters (outdoors) |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining, sandy or gravelly soil. Avoid heavy clay soils. | Well-draining soil, such as a sandy or gravelly loam. Avoid heavy clay soils. |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 15 minutes monthly (weeding, pruning) | 15 minutes weekly (outdoor) |
🔬 Botanical Information — Comparing These Plants
Myrtle Spurge
| Scientific Name | Euphorbia myrsinites |
|---|---|
| Family | Euphorbiaceae |
| Native To | Mediterranean region (Southern Europe and North Africa) |
| Also Known As | Myrtle Spurge, Donkey Spurge, Creeping Spurge, Glaucous Spurge |
| Leaves | Succulent, blue-gray, lance-shaped leaves arranged in a spiral pattern around the stems. Leaves are typically 1-2 inches long. |
| Flowers | Produces small, inconspicuous yellowish-green flowers in spring. Rarely flowers indoors. |
Penstemon
| Scientific Name | Penstemon spp. |
|---|---|
| Family | Plantaginaceae |
| Native To | North America, particularly western North America |
| Also Known As | Beardtongue, Penstemon |
| Leaves | Leaves are typically lance-shaped to oval, arranged oppositely along the stem. They can be smooth or slightly hairy, and vary in color from green to bluish-green. Leaf size varies depending on the species. |
| Flowers | Penstemon rarely flowers indoors due to insufficient light. Outdoors, they produce showy, tubular flowers in a wide range of colors, including blue, purple, pink, red, and white. Flowers are arranged in clusters or spikes at the ends of stems. |
📏 Size & Growth — Plant Comparison
Myrtle Spurge
Penstemon
🌱 Propagation — Comparing Plant Growth
Myrtle Spurge
Methods: Seed, Stem cuttings
Difficulty: Moderate
Tips: Take stem cuttings in spring or summer, allow the cut end to callous over for a few days, and then plant in well-draining soil. Wear gloves to avoid skin irritation from the sap.
Penstemon
Methods: Seed, stem cuttings, division
Difficulty: Moderate
Tips: For stem cuttings, take cuttings in late spring or early summer and root them in well-draining soil. Division can be done in early spring or fall. Seeds can be sown in spring or fall.
✨ Benefits & Features — Comparing Plant Value
Myrtle Spurge
The spirally arranged, blue-gray leaves give it a distinctive appearance. The milky sap is toxic and can cause skin irritation.
- ✓ Drought tolerance reduces water usage.
- ✓ Provides visual interest with its unique foliage.
- ✓ Low maintenance once established.
- ✓ Attracts pollinators.
- ✓ Controls erosion on slopes.
- ⚠️ Toxic to pets
Penstemon
Penstemon's tubular flowers are specifically adapted for pollination by bees and hummingbirds, showcasing a co-evolutionary relationship. The sterile stamen, or beardtongue, is a distinctive feature of the genus. Many species are native to specific regions and play important roles in local ecosystems.
- ✓ Attracts pollinators, supporting local ecosystems.
- ✓ Adds vibrant color and visual interest to gardens.
- ✓ Drought-tolerant, reducing water consumption.
- ✓ Relatively deer resistant, protecting from browsing.
- ✓ Provides a source of nectar for hummingbirds and bees.
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Myrtle Spurge
Penstemon
🌞 Light Requirements
Myrtle Spurge
Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth.
Low light tolerant: ❌ No
Penstemon
Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal flowering.
Low light tolerant: ❌ No
💧 Watering Needs
Myrtle Spurge
Water deeply but infrequently, allowing the soil to dry out completely between waterings. Overwatering can lead to root rot. Signs of underwatering include shriveled leaves. Signs of overwatering include yellowing leaves and a mushy stem.
Penstemon
Water deeply when the top inch of soil is dry. Avoid overwatering, as Penstemons are susceptible to root rot. Allow the soil to dry out slightly between waterings. Signs of overwatering include yellowing leaves and wilting, while underwatering can cause leaf drop and stunted growth.
🌡️ Temperature & Humidity
Myrtle Spurge
Temperature: 15-25°C
Humidity: 20-40%
Penstemon
Temperature: 15-27°C
Humidity: 30-50%
🤔 Which Plant Is Right For You?
Myrtle Spurge
Euphorbia myrsinitesExperienced gardeners looking for a drought-tolerant ground cover in sunny, well-drained locations.
✅ Choose This Plant If...
- You need a drought-tolerant ground cover for a sunny area.
- You appreciate the unique blue-gray foliage.
- You are an experienced gardener familiar with handling toxic plants.
- You want a low-maintenance plant once established.
- You have a rock garden or xeriscape landscape.
❌ Skip This Plant If...
- You have pets or small children who may ingest the plant.
- You are a beginner gardener.
- You do not have a sunny outdoor space.
- You are sensitive to latex or have skin allergies.
Penstemon
Penstemon spp.Gardeners looking for drought-tolerant, pollinator-attracting plants for sunny locations.
✅ Choose This Plant If...
- You want to attract hummingbirds and bees to your garden.
- You need a drought-tolerant plant for a sunny location.
- You desire a long-blooming perennial with vibrant colors.
- You want a plant that is relatively deer resistant.
- You are looking for a native plant to support local ecosystems.
❌ Skip This Plant If...
- You have pets that may ingest the plant.
- You cannot provide at least 6 hours of direct sunlight daily.
- You live in a humid climate with poorly draining soil.
🎯 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
Myrtle Spurge Care Tips
Myrtle Spurge is an outdoor plant that requires full sun and well-draining soil. It is not suitable for indoor growing due to its high light requirements and potential for toxicity. It is drought-tolerant and relatively low-maintenance once established, but requires careful handling due to its toxic sap.
- Always wear gloves and eye protection when handling Myrtle Spurge.
- Remove seed heads to prevent unwanted spread.
- Ensure excellent drainage to prevent root rot.
- Water deeply but infrequently.
- Provide full sun for optimal growth and color.
Penstemon Care Tips
Penstemon is primarily an outdoor plant that requires full sun and well-draining soil. It is not well-suited for indoor growing due to its high light requirements and need for specific environmental conditions. Indoor attempts are likely to fail without supplemental lighting and careful monitoring of soil moisture.
- Plant in well-draining soil to prevent root rot.
- Provide at least 6 hours of direct sunlight daily for optimal flowering.
- Deadhead spent flowers regularly to encourage more blooms.
- Water deeply but infrequently, allowing the soil to dry out slightly between waterings.
- Apply a balanced fertilizer in early spring before new growth begins.
⚠️ Common Problems & Solutions — Plant Care Comparison
Myrtle Spurge
Penstemon
❓ Frequently Asked Questions — Comparing These Plants
Myrtle Spurge
What are the light requirements for Myrtle Spurge?
Myrtle Spurge thrives in bright, direct sunlight. Aim for at least 6 hours of sunlight per day. An east- or south-facing window is ideal. If grown outdoors, choose a location that receives full sun. Insufficient light can lead to etiolation, where the plant stretches towards the light source, resulting in weak, leggy growth. Rotate the plant regularly to ensure even light exposure on all sides. In regions with intense summer sun, provide some afternoon shade to prevent scorching. Supplement with grow lights if natural light is limited, particularly during winter months.
How do I care for Myrtle Spurge?
Myrtle Spurge requires well-draining soil, such as a cactus or succulent mix, to prevent root rot. Water thoroughly when the soil is completely dry, typically every 2-4 weeks, depending on environmental conditions. Provide bright, direct sunlight for at least 6 hours a day; however, protect it from intense afternoon sun in hot climates. Fertilize sparingly, only during the growing season (spring and summer), using a balanced, diluted succulent fertilizer. Prune dead or damaged leaves to maintain its appearance. Be extremely cautious of the milky sap, which can cause skin irritation. Wear gloves when handling. Avoid overwatering, especially during winter dormancy.
How do I propagate Myrtle Spurge?
Myrtle Spurge can be propagated through stem cuttings, leaf cuttings, or offsets. For stem cuttings, allow the cut end to callous over for a few days before planting in well-draining soil. Rooting hormone can aid in the process. Leaf cuttings can be placed on top of well-draining soil and misted occasionally. Offsets, or small plantlets that grow around the base of the mother plant, can be carefully separated and potted individually. Wear gloves when handling cuttings to avoid skin irritation from the sap. Provide bright, indirect light and maintain consistent moisture until roots develop. Propagation is best done during the growing season (spring or summer).
Penstemon
What are the light requirements for Penstemon?
Penstemon requires at least six hours of direct sunlight per day to thrive and produce abundant blooms. A location with full sun exposure is ideal. If growing Penstemon indoors, place it near a sunny window, preferably a south-facing one. Insufficient light can result in leggy growth, reduced flowering, and pale foliage. In hot climates, some afternoon shade may be beneficial to prevent scorching. Rotate the plant regularly to ensure even light exposure on all sides. Consider using grow lights to supplement natural light during the darker months of the year, especially for indoor plants.
How do I care for Penstemon?
Penstemon thrives in well-draining soil and prefers full sun, although some varieties can tolerate partial shade. Water regularly during the first growing season to establish a strong root system, then reduce watering frequency as the plant matures. Avoid overwatering, as this can lead to root rot. Fertilize in early spring with a balanced fertilizer to promote healthy growth and abundant blooms. Deadhead spent flowers to encourage continuous blooming. Prune back in late fall or early spring to maintain shape and remove any dead or damaged growth. Provide good air circulation to prevent fungal diseases. Mulch around the base of the plant to conserve moisture and suppress weeds. Penstemon is generally hardy but may benefit from winter protection in colder climates.
How do I propagate Penstemon?
Penstemon can be propagated by division, stem cuttings, and seeds.
Last updated: May 2, 2026 — Plant care data reviewed and verified by our editorial team.