Oxalis vs Pulmonaria Plant Comparison

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

Oxalis

Oxalis

Oxalis triangularis

VS
Pulmonaria

Pulmonaria

Pulmonaria officinalis

Oxalis

Oxalis

Oxalis triangularis

Oxalis triangularis is a rhizomatous perennial plant known for its distinctive triangular, purple leaves that resemble shamrocks. These leaves exhibit nyctinastic movement, folding up at night and opening during the day in response to light. It's commonly grown as a houseplant for its unique foliage and relatively easy care. While it can be grown outdoors in suitable climates, it's more often seen as an indoor plant due to its sensitivity to frost. People grow it for its striking appearance and the interesting movement of its leaves.

Oxalidaceae Brazil
✨ Features: Nyctinastic leaf movement (folding at night), striking purple foliage.
📖 Read Complete Oxalis 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 Oxalis Pulmonaria
Light Bright indirect light to partial shade. Can tolerate some direct morning sun. Partial shade to full shade. Avoid direct sunlight, especially during the hottest part of the day.
Watering Every 7-10 days, depending on environmental conditions Every 3-5 days, depending on environmental conditions
Humidity 40-60% 40-60%
Temperature 18-24°C 13-18°C
Care Level Easy Expert
Growth Rate Moderate Moderate
Max Height 20-30 cm 20-30 cm (indoors unlikely to reach this)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining potting mix, such as a mix of peat moss, perlite, and vermiculite. Well-draining, humus-rich soil
Beginner Friendly ✅ Yes ❌ No
Weekly Maintenance 5-10 minutes weekly 15 minutes weekly (outdoor)

🔬 Botanical Information — Comparing These Plants

Oxalis

Scientific Name Oxalis triangularis
Family Oxalidaceae
Native To Brazil
Also Known As Purple Shamrock, False Shamrock, Love Plant
Leaves The leaves are triangular in shape, with three leaflets resembling shamrocks. They are typically a deep purple color, although some varieties have green or variegated leaves. The leaves are smooth and delicate in appearance.
Flowers Oxalis triangularis can produce small, trumpet-shaped flowers, usually white or pale pink. Flowering is more common during the spring and summer months, but may not occur frequently indoors.

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

Oxalis

Height 20-30 cm
Spread 30-45 cm
Growth Rate Moderate
Growth Pattern Oxalis triangularis grows in a clumping habit from rhizomes. It produces upright stems that support the triangular leaves. It can spread slowly over time as the rhizomes multiply.

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

Oxalis

Methods: Division, Rhizome cuttings, Seed

Difficulty: Easy

Tips: Divide rhizomes during repotting. Plant rhizome cuttings in well-draining soil and keep moist until new growth appears. Seeds can be sown in spring.

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

Oxalis

The most unique characteristic of Oxalis triangularis is its nyctinastic leaf movement, where the leaves fold up at night and open during the day. Its striking purple, triangular leaves also make it a visually distinctive houseplant.

  • ✓ Adds a pop of color to any room.
  • ✓ Easy to propagate and share with friends.
  • ✓ Relatively low-maintenance and forgiving.
  • ✓ Provides a unique visual interest with its leaf movement.
  • ✓ Can be grown in a variety of containers.
  • ⚠️ 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

Oxalis

Repotting Every 1-2 years, or when the plant becomes root-bound.
Pruning Remove any dead or damaged leaves to maintain appearance and prevent disease.
Fertilizing Balanced liquid fertilizer (20-20-20) diluted to half strength, every 4-6 weeks during the growing season (spring and summer).
Seasonal Care During the growing season (spring and summer), water regularly and fertilize every 4-6 weeks. In the fall and winter, reduce watering and allow the plant to go dormant if it chooses to. The leaves may die back, but the rhizomes will remain alive.

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

Oxalis

Bright indirect light to partial shade. Can tolerate some direct morning sun.

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

Oxalis

Water thoroughly when the top inch of soil feels dry. Allow excess water to drain away. Overwatering can lead to root rot, indicated by yellowing or wilting leaves. Underwatering will cause the leaves to droop and become crispy.

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

Oxalis

Temperature: 18-24°C

Humidity: 40-60%

Pulmonaria

Temperature: 13-18°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Oxalis

Oxalis

Oxalis triangularis
Care: Easy Time: 5-10 minutes weekly Beginner: Yes

Plant enthusiasts looking for a visually striking and relatively low-maintenance houseplant.

✅ Choose This Plant If...

  • You want a plant with unique, eye-catching foliage.
  • You enjoy plants that exhibit interesting behaviors, like leaf movement.
  • You're looking for a relatively low-maintenance houseplant.
  • You have a bright, indirect light location.
  • You want a plant that can be easily propagated.

❌ Skip This Plant If...

  • You have pets that are prone to eating plants.
  • You tend to overwater your plants.
  • You don't have a location with bright, indirect light.
📍 Ideal Location: Bright windowsill, shelf, or table in a room with indirect light.
🎨 Style: Modern, Bohemian, Eclectic
🏠 Apartment Friendly: Yes
⚠️ Oxalic acid is present in all parts of the plant, especially the leaves. It is toxic to dogs, cats, and horses. Symptoms include drooling, vomiting, diarrhea, and loss of appetite. In rare cases, kidney failure can occur.
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 Oxalis
Pet Friendly Neither - caution
Less Maintenance Oxalis
Apartment Friendly Oxalis

⚡ Key Differences Between These Plants

🎯

Oxalis is rated Easy care level, while Pulmonaria is Expert.

💡 Pro Tips For Comparing These Plants

Oxalis Care Tips

Oxalis triangularis is relatively easy to care for indoors. It requires bright indirect light, well-draining soil, and regular watering. It can go dormant in the winter, during which time watering should be reduced. Its sensitivity to overwatering is the main challenge.

  • Rotate the plant regularly to ensure even growth.
  • Allow the soil to dry slightly between waterings to prevent root rot.
  • Fertilize regularly during the growing season to promote healthy growth.
  • Provide bright, indirect light to maintain the vibrant purple color of the leaves.
  • If the plant goes dormant, reduce watering and allow it to rest in a cool, dark place.
❄️ Winter: Reduce watering significantly during the winter months. If the plant goes dormant, allow the leaves to die back and store the rhizomes in a cool, dark place until spring. If the plant continues to grow, provide bright, indirect light and water sparingly.
☀️ Summer: Provide bright, indirect light and water regularly during the summer months. Fertilize every 4-6 weeks to promote healthy growth. Protect the plant from intense direct sunlight, which can scorch the leaves.

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

Oxalis

Common Issues: Root rot, Spider mites, Dormancy
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Spider mites: Treat with insecticidal soap or neem oil. Dormancy: Reduce watering and allow the plant to rest in a cool, dark place.

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

Oxalis

What are the light requirements for Oxalis?

Oxalis plants need bright, indirect light to thrive. Too little light will cause the leaves to become pale and the stems to become leggy. Too much direct sunlight can scorch the leaves, causing brown spots. An ideal location for your Oxalis is near an east- or west-facing window, where it will receive plenty of bright, indirect light without being exposed to harsh direct sunlight.

How do I care for Oxalis?

Oxalis plants thrive in bright, indirect light. Direct sunlight can scorch their delicate leaves, so a location near an east- or west-facing window is ideal. Water your Oxalis when the top inch of soil feels dry to the touch. Avoid overwatering, as this can lead to root rot. Use well-draining potting mix to ensure proper drainage. Fertilize your Oxalis every 2-4 weeks during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength.

How do I propagate Oxalis?

Oxalis can be easily propagated through division. Carefully dig up the plant and separate the bulbs or rhizomes. Replant the separated bulbs or rhizomes in individual pots filled with well-draining potting mix. Water thoroughly and place in a bright location with indirect light. Keep the soil consistently moist until new growth appears.

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: April 28, 2026 — Plant care data reviewed and verified by our editorial team.