Lobelia Cardinalis vs Pulmonaria Plant Comparison

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

Lobelia Cardinalis

Lobelia Cardinalis

Lobelia cardinalis

VS
Pulmonaria

Pulmonaria

Pulmonaria officinalis

Lobelia Cardinalis

Lobelia Cardinalis

Lobelia cardinalis

Lobelia cardinalis, the Cardinal flower, is a striking herbaceous perennial native to North America. It features vibrant red, tubular flowers arranged on tall spikes, reaching heights of 2-4 feet. The plant has lance-shaped, green leaves that provide a lush backdrop to the brilliant blooms. It thrives in moist, well-drained soil and prefers partial shade to full sun. Cardinal flowers are primarily grown for their showy flowers, which attract hummingbirds and butterflies, making them a popular choice for gardens and naturalized areas. While it can be grown in containers, it is primarily an outdoor plant and may struggle indoors.

Campanulaceae North America
✨ Features: Attracts hummingbirds and butterflies, showy red flowers
📖 Read Complete Lobelia Cardinalis Guide
Pulmonaria

Pulmonaria

Pulmonaria officinalis

Pulmonaria officinalis, commonly known as lungwort, is a herbaceous perennial plant native to Europe. It is characterized by its distinctive spotted leaves, which are typically green with white or silver markings. The plant forms a low-growing clump and produces clusters of small, bell-shaped flowers that change color from pink to blue as they mature. Lungwort is primarily grown outdoors in gardens for its attractive foliage and early spring blooms. It thrives in shady, woodland-like conditions. While it can be attempted indoors, it requires very specific conditions and is generally not well-suited for indoor cultivation.

Boraginaceae Europe
✨ Features: Attracts pollinators, deer-resistant, unique spotted foliage, color-changing flowers
📖 Read Complete Pulmonaria Guide

Quick Plant Comparison

Feature Lobelia Cardinalis Pulmonaria
Light Partial shade to full sun (at least 6 hours of direct sunlight) Partial shade to full shade. Avoid direct sunlight, especially during the hottest part of the day.
Watering Every 2-3 days, depending on weather and soil drainage Every 3-5 days, depending on environmental conditions
Humidity 40-60% 40-60%
Temperature 15-25°C 13-18°C
Care Level Expert Expert
Growth Rate Moderate Moderate
Max Height 0.6-1.2 meters (2-4 feet) 20-30 cm (indoors unlikely to reach this)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Rich, well-drained soil with plenty of organic matter Well-draining, humus-rich soil
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 15 minutes weekly (outdoor)

🔬 Botanical Information — Comparing These Plants

Lobelia Cardinalis

Scientific Name Lobelia cardinalis
Family Campanulaceae
Native To North America
Also Known As Cardinal flower, Red lobelia
Leaves Lance-shaped, medium green leaves with serrated edges. Leaves are typically 7-15 cm long and arranged alternately along the stem.
Flowers Flowers are bright red, tubular, and arranged in a spike-like raceme. They bloom from mid-summer to early fall. It is highly unlikely to flower indoors due to light requirements.

Pulmonaria

Scientific Name Pulmonaria officinalis
Family Boraginaceae
Native To Europe
Also Known As Lungwort, Common Lungwort, Jerusalem Cowslip, Spotted Dog
Leaves The leaves of Pulmonaria are ovate to lance-shaped, typically 10-25 cm long, and have a rough texture. They are usually green with distinctive white or silver spots, although some varieties have more pronounced variegation. The spots are caused by air pockets within the leaf tissue.
Flowers Pulmonaria produces clusters of small, bell-shaped flowers in early spring. The flowers are typically pink when they first open, then gradually turn blue as they mature. This color change is due to changes in pH levels within the petals. Flowering is unlikely indoors.

📏 Size & Growth — Plant Comparison

Lobelia Cardinalis

Height 0.6-1.2 meters (2-4 feet)
Spread 30-60 cm (1-2 feet)
Growth Rate Moderate
Growth Pattern Upright, clumping perennial with tall flower spikes.

Pulmonaria

Height 20-30 cm (indoors unlikely to reach this)
Spread 30-45 cm (spreads via rhizomes)
Growth Rate Moderate
Growth Pattern Pulmonaria grows as a low-growing clump, spreading slowly via rhizomes. It forms a dense mat of foliage and produces upright flower stalks in the spring.

🌱 Propagation — Comparing Plant Growth

Lobelia Cardinalis

Methods: Seed, Division, Stem cuttings

Difficulty: Moderate

Tips: For seeds, cold stratify for 30 days before sowing. Divide clumps in spring or fall. Take stem cuttings in late spring and root in moist soil.

Pulmonaria

Methods: Division, Seed

Difficulty: Moderate

Tips: Divide established clumps in early spring or fall. Sow seeds in a cold frame in autumn or early spring.

✨ Benefits & Features — Comparing Plant Value

Lobelia Cardinalis

The vibrant red color and tubular shape of the flowers are specifically adapted to attract hummingbirds. It is a native plant that supports local ecosystems and provides habitat for wildlife.

  • ✓ Attracts pollinators (hummingbirds, butterflies)
  • ✓ Adds vibrant color to the garden
  • ✓ Provides habitat for wildlife
  • ✓ Native plant supports local ecosystems
  • ✓ Can be used in cut flower arrangements
  • ⚠️ Toxic to pets

Pulmonaria

The most unique characteristic of Pulmonaria is its spotted leaves, which provide visual interest even when the plant is not in bloom. The flowers also change color from pink to blue as they mature, adding another layer of appeal. It is also relatively deer-resistant.

  • ✓ Attracts pollinators to your garden.
  • ✓ Adds visual interest with its unique spotted foliage.
  • ✓ Provides early spring color to shady areas.
  • ✓ Deer-resistant, protecting your garden from damage.
  • ✓ Can be used as a ground cover in woodland gardens.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Lobelia Cardinalis

Repotting Not applicable as it's primarily an outdoor plant. If grown in containers, repot every 2-3 years in spring.
Pruning Deadhead spent flowers to encourage continued blooming. Cut back to the base in late fall after the foliage has died back.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, applied monthly during the growing season (spring and summer)
Seasonal Care In spring, divide clumps to propagate. In summer, provide consistent moisture and fertilize regularly. In fall, cut back spent flower spikes. In winter, mulch to protect from frost.

Pulmonaria

Repotting Not applicable for indoor growing due to unsuitability. If grown in a container outdoors, repot every 2-3 years.
Pruning Remove dead or damaged leaves as needed. Cut back after flowering to encourage new growth.
Fertilizing Balanced liquid fertilizer diluted to half strength, applied once in early spring.
Seasonal Care In spring, fertilize and monitor for pests. In summer, provide shade and consistent moisture. In fall, divide plants if needed. In winter, protect from frost in colder climates.

🌞 Light Requirements

Lobelia Cardinalis

Partial shade to full sun (at least 6 hours of direct sunlight)

Low light tolerant: ❌ No

Pulmonaria

Partial shade to full shade. Avoid direct sunlight, especially during the hottest part of the day.

Low light tolerant: ❌ No

💧 Watering Needs

Lobelia Cardinalis

Keep the soil consistently moist, especially during hot weather. Water deeply when the top inch of soil feels dry. Overwatering can lead to root rot, indicated by yellowing leaves and a musty smell. Underwatering results in wilting and dry, crispy leaves.

Pulmonaria

Keep the soil consistently moist, but not waterlogged. Water when the top inch of soil feels dry to the touch. Overwatering can lead to root rot, while underwatering can cause the leaves to wilt and brown. Ensure good drainage.

🌡️ Temperature & Humidity

Lobelia Cardinalis

Temperature: 15-25°C

Humidity: 40-60%

Pulmonaria

Temperature: 13-18°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Lobelia Cardinalis

Lobelia Cardinalis

Lobelia cardinalis
Care: Expert Time: 15 minutes weekly Beginner: No

Gardeners looking to attract hummingbirds and butterflies to their moist, partially shaded gardens.

✅ Choose This Plant If...

  • You want to attract hummingbirds to your garden.
  • You have a moist, partially shaded area in your yard.
  • You appreciate vibrant red flowers.
  • You enjoy native North American plants.
  • You want a plant that adds vertical interest to your garden.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You have a dry garden.
  • You are looking for a low-maintenance indoor plant.
📍 Ideal Location: Outdoor garden or naturalized area with moist soil and partial shade.
🎨 Style: Cottage, Naturalistic, Woodland
🏠 Apartment Friendly: No
⚠️ All parts of the plant are toxic to dogs, cats, and horses. Symptoms include nausea, vomiting, diarrhea, and in severe cases, respiratory paralysis. The toxic compounds are alkaloids.
Pulmonaria

Pulmonaria

Pulmonaria officinalis
Care: Expert Time: 15 minutes weekly (outdoor) Beginner: No

Experienced gardeners looking for a shade-loving plant with unique foliage and early spring blooms in an outdoor garden.

✅ Choose This Plant If...

  • You want a shade-loving plant with unique spotted foliage.
  • You appreciate early spring blooms that attract pollinators.
  • You are looking for a deer-resistant plant for your garden.
  • You enjoy plants with interesting color-changing flowers.
  • You have a cool, shady spot in your garden that needs some color.

❌ Skip This Plant If...

  • You are looking for an easy-to-grow indoor plant.
  • You have pets that might ingest the plant.
  • You do not have a cool, shady outdoor space.
📍 Ideal Location: Outdoor shade garden or woodland garden. Not suitable for typical indoor environments.
🎨 Style: Woodland, Cottage, Traditional
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Pulmonaria species contain pyrrolizidine alkaloids, which are toxic to dogs, cats, and horses. Symptoms include liver damage, abdominal pain, vomiting, and diarrhea. The entire plant is considered 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

Lobelia Cardinalis Care Tips

Lobelia cardinalis is primarily an outdoor plant that requires consistent moisture and partial to full sun. Indoor cultivation is challenging due to the need for high light levels and humidity. It is prone to root rot if overwatered and requires regular fertilization during the growing season. It is also toxic to pets.

  • Provide consistent moisture, especially during hot weather.
  • Deadhead spent flowers to encourage more blooms.
  • Divide clumps every few years to prevent overcrowding.
  • Protect from slugs and snails.
  • Mulch around the base of the plant to retain moisture and suppress weeds.
❄️ Winter: Cut back the foliage to the base after it dies back in the fall. Mulch around the base of the plant to protect the roots from frost.
☀️ Summer: Provide consistent moisture, especially during hot weather. Fertilize monthly with a balanced liquid fertilizer. Monitor for pests such as aphids and slugs.

Pulmonaria Care Tips

Pulmonaria is primarily an outdoor plant that prefers cool, shady conditions. Indoor cultivation is challenging due to the need for consistent moisture, high humidity, and cool temperatures. It is prone to fungal diseases and root rot if not properly cared for indoors. Requires very bright indirect light, which is difficult to provide indoors.

  • Provide consistent moisture, especially during dry periods.
  • Protect from direct sunlight to prevent leaf scorch.
  • Amend the soil with compost or leaf mold to improve drainage and fertility.
  • Divide plants every few years to prevent overcrowding.
  • Monitor for pests and diseases regularly.
❄️ Winter: In colder climates, protect Pulmonaria from frost by mulching around the base of the plant. Reduce watering during the dormant season.
☀️ Summer: Provide shade during the hottest part of the day to prevent leaf scorch. Ensure consistent moisture, especially during dry periods.

⚠️ Common Problems & Solutions — Plant Care Comparison

Lobelia Cardinalis

Common Issues: Root rot, Aphids, Powdery mildew, Slugs and snails
Solutions: Root rot: Improve drainage and reduce watering frequency. Aphids: Spray with insecticidal soap. Powdery mildew: Improve air circulation and apply fungicide. Slugs and snails: Use slug bait or handpick.

Pulmonaria

Common Issues: Powdery mildew, Slugs and snails, Root rot, Leaf spot
Solutions: Improve air circulation and apply fungicide for powdery mildew. Use slug and snail bait or handpick pests. Ensure good drainage and avoid overwatering to prevent root rot. Remove affected leaves for leaf spot and apply fungicide if necessary.

❓ Frequently Asked Questions — Comparing These Plants

Lobelia Cardinalis

What are the light requirements for Lobelia Cardinalis?

Lobelia Cardinalis prefers bright, indirect light. While it can tolerate some morning sun, intense afternoon sun can scorch the leaves, especially in hotter climates. When grown indoors, place the plant near an east-facing or west-facing window where it will receive ample light without direct exposure. If you don’t have access to natural light, consider using a grow light to supplement its needs. Insufficient light can lead to leggy growth and reduced flowering. Rotate the plant regularly to ensure even light exposure on all sides. Watch for signs of overexposure, such as bleached or burned leaves, and adjust the plant’s location accordingly.

How do I care for Lobelia Cardinalis?

Lobelia Cardinalis thrives in consistently moist soil, ideally rich in organic matter. Water regularly, especially during dry periods, ensuring the soil doesn’t dry out completely. Provide bright, indirect light; direct sunlight can scorch the leaves. Fertilize every 2-4 weeks during the growing season (spring and summer) with a balanced liquid fertilizer, diluted to half strength. Deadhead spent flowers to encourage continued blooming. Maintain a humid environment, especially if growing indoors; consider using a humidifier or placing the plant on a pebble tray filled with water. Protect from frost in colder climates, either by bringing it indoors or providing adequate winter protection. Repot in spring if the plant becomes root-bound. Monitor for pests such as aphids and spider mites, and treat promptly if necessary. Propagate by seed, division, or stem cuttings.

How do I propagate Lobelia Cardinalis?

Lobelia Cardinalis can be propagated by division, stem cuttings, or seeds. For division, carefully separate the plant into smaller clumps in early spring, ensuring each clump has roots and foliage. Replant the divisions in moist, well-draining soil. For stem cuttings, take 4-6 inch cuttings from healthy stems in spring or summer. Remove the lower leaves and place the cuttings in water or moist potting mix until roots develop. Once rooted, transplant into pots. Seeds can be sown indoors in early spring or directly outdoors after the last frost. Keep the soil consistently moist until germination.

Pulmonaria

What are the light requirements for Pulmonaria?

Pulmonaria thrives in partial to full shade. In regions with hot summers, full shade is essential to prevent leaf scorch. Morning sun is tolerated, but avoid direct afternoon sun. The ideal location receives dappled sunlight throughout the day. Insufficient light can result in fewer blooms and less vibrant foliage.

How do I care for Pulmonaria?

Pulmonaria prefers partial to full shade, especially in warmer climates. Direct sunlight can scorch the leaves. The ideal location is one that receives morning sun and afternoon shade. Plant in well-draining, humus-rich soil that retains moisture. Water regularly, especially during dry periods, keeping the soil consistently moist but not soggy.

How do I propagate Pulmonaria?

Pulmonaria is most easily propagated by division in early spring or fall. Carefully dig up the plant and separate the root ball into smaller clumps, ensuring each clump has healthy roots and foliage. Replant the divisions in well-draining, humus-rich soil. Keep the soil consistently moist until the plants are established.

Last updated: May 15, 2026 — Plant care data reviewed and verified by our editorial team.