Perennial Flax vs Stock Plant Comparison

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

Perennial Flax

Perennial Flax

Linum perenne

VS
Stock

Stock

Matthiola incana

Perennial Flax

Perennial Flax

Linum perenne

Perennial Flax (Linum perenne) is a herbaceous perennial known for its delicate, airy appearance and profuse display of sky-blue flowers. It typically grows to a height of 30-60 cm. The plant features slender stems and narrow, lance-shaped leaves. While primarily an outdoor plant, it is grown for its ornamental value in gardens and meadows, attracting pollinators. The flowers are short-lived, opening in the morning and closing by afternoon, but the plant produces a continuous succession of blooms throughout the flowering season. It is not naturally an indoor plant.

Linaceae Europe, North Africa, Asia
✨ Features: Attracts pollinators, drought-tolerant once established
📖 Read Complete Perennial Flax Guide
Stock

Stock

Matthiola incana

Matthiola incana, commonly known as Stock, is an herbaceous annual or biennial plant typically grown for its intensely fragrant and showy flowers. It features upright stems with lance-shaped, grayish-green leaves. The flowers are densely packed in terminal spikes and come in a wide range of colors, including white, pink, purple, red, and yellow. While primarily an outdoor plant, some cultivars can be grown indoors with significant effort to replicate outdoor conditions. People grow it for its beautiful flowers and strong, sweet fragrance, often used in bouquets and gardens.

Brassicaceae Southern Europe and the Mediterranean region
✨ Features: Intensely fragrant flowers, wide range of colors, attracts pollinators.
📖 Read Complete Stock Guide

Quick Plant Comparison

Feature Perennial Flax Stock
Light Full sun Full sun (at least 6 hours of direct sunlight per day)
Watering Every 7-10 days, depending on weather and soil drainage Every 2-5 days outdoors, less frequently indoors depending on light and temperature.
Humidity 30-50% 40-60%
Temperature 15-24°C 15-21°C
Care Level Expert Expert
Growth Rate Moderate Moderate
Max Height N/A (Outdoor plant, not suitable for indoor growing) Indoors: 30-60 cm (1-2 feet). Outdoors: 30-80 cm (1-2.5 feet)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining, sandy or loamy soil Well-draining, fertile soil. A mix of potting soil, perlite, and compost is suitable.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 5 minutes weekly 15 minutes weekly

🔬 Botanical Information — Comparing These Plants

Perennial Flax

Scientific Name Linum perenne
Family Linaceae
Native To Europe, North Africa, Asia
Also Known As Perennial Flax, Blue Flax, Flax
Leaves Narrow, lance-shaped leaves, typically blue-green in color, arranged alternately along the stems.
Flowers Flowers are typically sky-blue, about 2.5 cm in diameter, with five petals. They open in the morning and close by afternoon. Rarely flowers indoors.

Stock

Scientific Name Matthiola incana
Family Brassicaceae
Native To Southern Europe and the Mediterranean region
Also Known As Stock, Gillyflower, Tenweeks Stock
Leaves Lance-shaped, grayish-green leaves with a slightly hairy texture. The leaves are typically 5-10 cm (2-4 inches) long and arranged alternately along the stems.
Flowers Stock flowers can bloom indoors if provided with sufficient light, but it is rare. Outdoors, the flowers are densely packed in terminal spikes and come in a wide range of colors, including white, pink, purple, red, and yellow. They have a strong, sweet fragrance.

📏 Size & Growth — Plant Comparison

Perennial Flax

Height N/A (Outdoor plant, not suitable for indoor growing)
Spread 30-45 cm
Growth Rate Moderate
Growth Pattern Upright, clumping perennial with slender stems and airy foliage.

Stock

Height Indoors: 30-60 cm (1-2 feet). Outdoors: 30-80 cm (1-2.5 feet)
Spread 20-30 cm (8-12 inches)
Growth Rate Moderate
Growth Pattern Upright, branching stems with a bushy growth habit. The flowers are densely packed in terminal spikes, creating a showy display.

🌱 Propagation — Comparing Plant Growth

Perennial Flax

Methods: Seed, Division

Difficulty: Easy

Tips: Sow seeds in spring or fall. Divide established plants in spring or fall. Ensure good drainage for successful propagation.

Stock

Methods: Seed

Difficulty: Easy

Tips: Sow seeds indoors 6-8 weeks before the last expected frost or directly outdoors after the danger of frost has passed. Provide consistent moisture and warmth for germination.

✨ Benefits & Features — Comparing Plant Value

Perennial Flax

Perennial Flax is known for its delicate, blue flowers that open in the morning and close by afternoon. It is a relatively low-maintenance perennial that attracts pollinators and is drought-tolerant once established.

  • ✓ Attracts pollinators like bees and butterflies.
  • ✓ Adds a delicate, airy texture to the garden.
  • ✓ Provides a long season of blue flowers.
  • ✓ Drought-tolerant once established, reducing water needs.
  • ✓ Relatively low-maintenance, freeing up gardening time.
  • ⚠️ Toxic to pets

Stock

Stock is known for its intensely fragrant flowers, which have a sweet and spicy scent. The flowers come in a wide range of colors, making it a popular choice for gardens and bouquets. It is also relatively cold-hardy compared to other flowering annuals.

  • ✓ Beautiful and fragrant flowers enhance the aesthetic appeal of gardens and homes.
  • ✓ Attracts pollinators like bees and butterflies, supporting local ecosystems.
  • ✓ Can be used in cut flower arrangements, bringing beauty indoors.
  • ✓ The sweet fragrance can have a calming and mood-boosting effect.
  • ✓ Provides a rewarding gardening experience for those who enjoy nurturing plants.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Perennial Flax

Repotting N/A (Outdoor plant)
Pruning Deadhead spent flowers regularly to encourage continued blooming. Cut back stems in fall after flowering.
Fertilizing Balanced slow-release fertilizer in spring
Seasonal Care In spring, apply a balanced fertilizer. In summer, deadhead spent flowers to encourage more blooms. In fall, cut back stems after flowering. In winter, provide protection from excessive moisture.

Stock

Repotting Not typically needed as it's an annual or biennial. If grown in a container, repot in spring if the plant becomes root-bound.
Pruning Deadhead spent flowers regularly to encourage more blooms. Prune back stems to maintain shape and promote bushier growth.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-4 weeks during the growing season.
Seasonal Care Spring/Summer: Regular watering and fertilization. Provide support for tall stems. Fall: Deadhead spent flowers to prolong blooming. Winter: Reduce watering and provide protection from frost if grown outdoors.

🌞 Light Requirements

Perennial Flax

Full sun

Low light tolerant: ❌ No

Stock

Full sun (at least 6 hours of direct sunlight per day)

Low light tolerant: ❌ No

💧 Watering Needs

Perennial Flax

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Ensure good drainage. Signs of underwatering include wilting and yellowing leaves. Overwatering can cause root rot and fungal diseases.

Stock

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Ensure good drainage. Signs of overwatering include yellowing leaves and a musty smell. Underwatering is indicated by wilting and dry, crispy leaves.

🌡️ Temperature & Humidity

Perennial Flax

Temperature: 15-24°C

Humidity: 30-50%

Stock

Temperature: 15-21°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Perennial Flax

Perennial Flax

Linum perenne
Care: Expert Time: 5 minutes weekly Beginner: No

Gardeners looking for a low-maintenance, flowering perennial for sunny locations.

✅ Choose This Plant If...

  • You want a low-maintenance perennial for a sunny garden.
  • You want to attract pollinators to your garden.
  • You appreciate delicate, blue flowers.
  • You have well-draining soil.
  • You live in a climate with mild winters.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You don't have a sunny outdoor space.
  • You are looking for an easy indoor plant.
📍 Ideal Location: Sunny garden bed or border
🎨 Style: Cottage, Naturalistic, Mediterranean
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, flax (Linum species) is toxic to dogs, cats, and horses. The toxic principle is cyanogenic glycosides. Symptoms include vomiting, diarrhea, weakness, and difficulty breathing. The seeds are the most toxic part.
Stock

Stock

Matthiola incana
Care: Expert Time: 15 minutes weekly Beginner: No

Experienced gardeners who want to grow fragrant flowers outdoors or are willing to provide the necessary conditions for indoor cultivation.

✅ Choose This Plant If...

  • You love fragrant flowers and want to add a sweet scent to your garden.
  • You enjoy cut flowers and want to grow your own bouquets.
  • You have a sunny outdoor space where you can provide the plant with ample light.
  • You are an experienced gardener and enjoy a challenge.
  • You want to attract pollinators to your garden.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You don't have a sunny location or the means to provide supplemental lighting for indoor growing.
  • You are a beginner gardener looking for an easy-to-care-for plant.
📍 Ideal Location: Outdoors: Sunny garden beds or containers. Indoors: South-facing window with supplemental lighting.
🎨 Style: Cottage, Romantic, Traditional
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Stock (Matthiola spp.) contains glucosinolates which can cause mild gastrointestinal upset in dogs, cats, and horses. Symptoms include vomiting, diarrhea, and drooling. All parts of the plant are potentially 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

☀️

Perennial Flax needs full sun, while Stock prefers full sun (at least 6 hours of direct sunlight per day).

📈

Perennial Flax has moderate growth, while Stock grows moderate.

💡 Pro Tips For Comparing These Plants

Perennial Flax Care Tips

Perennial Flax is primarily an outdoor plant and is challenging to grow indoors due to its high light requirements. It needs full sun and well-draining soil. Indoor attempts often result in leggy growth and poor flowering. It is toxic to pets.

  • Ensure well-draining soil to prevent root rot.
  • Provide full sun for optimal flowering.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Apply a balanced fertilizer in spring.
  • Protect from excessive moisture in winter.
❄️ Winter: Cut back stems after flowering. Provide protection from excessive moisture.
☀️ Summer: Deadhead spent flowers regularly to encourage more blooms. Water thoroughly when the top inch of soil feels dry.

Stock Care Tips

Stock is primarily an outdoor plant and requires full sun and well-drained soil. Growing it indoors is challenging due to the high light requirements. Supplemental lighting is often necessary. Consistent watering and fertilization are crucial for healthy growth and abundant flowering.

  • Provide support for tall stems to prevent them from bending or breaking.
  • Deadhead spent flowers regularly to encourage continuous blooming.
  • Ensure good air circulation to prevent fungal diseases.
  • Water deeply but infrequently, allowing the soil to dry slightly between waterings.
  • Fertilize regularly during the growing season to promote healthy growth and abundant flowering.
❄️ Winter: If grown as a biennial, protect from frost with mulch or by moving containers indoors. Reduce watering during the dormant period.
☀️ Summer: Provide regular watering and fertilization. Protect from intense afternoon sun in hot climates. Deadhead spent flowers to prolong blooming.

⚠️ Common Problems & Solutions — Plant Care Comparison

Perennial Flax

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

Stock

Common Issues: Aphids, spider mites, fungal diseases (e.g., powdery mildew, root rot), leggy growth due to insufficient light.
Solutions: Aphids/spider mites: Insecticidal soap or neem oil. Fungal diseases: Improve air circulation, avoid overwatering, and use a fungicide if necessary. Leggy growth: Provide more light or prune back stems to encourage bushier growth.

❓ Frequently Asked Questions — Comparing These Plants

Perennial Flax

What are the light requirements for Perennial Flax?

Perennial Flax requires a minimum of six hours of direct sunlight per day to thrive and produce abundant blooms. A south-facing location is ideal, but east or west-facing exposures can also work if they provide sufficient sunlight. Insufficient light can lead to leggy growth, reduced flowering, and pale foliage. If growing indoors, place the plant near a sunny window or supplement with artificial grow lights. Rotate the plant regularly to ensure even light exposure on all sides. When transplanting, choose a location that receives full sun throughout the day. Be mindful of shadows cast by trees or buildings, especially during the shorter days of winter.

How do I care for Perennial Flax?

Perennial Flax thrives in full sun and well-drained soil. Water deeply but infrequently, allowing the soil to dry out between waterings. Amend heavy clay soils with compost or other organic matter to improve drainage. Fertilize lightly in spring with a balanced fertilizer to encourage blooming. Deadhead spent flowers to promote continued flowering. Cut back the plant after blooming to maintain its shape and encourage bushier growth. Provide support if necessary, as the stems can become leggy. Protect from excessive winter moisture in colder climates. Mulch around the base of the plant to retain moisture and suppress weeds. Monitor for pests and diseases, and treat promptly if necessary. Divide established plants every few years to rejuvenate them.

How do I propagate Perennial Flax?

Perennial Flax can be propagated by seed, division, or stem cuttings.

Stock

What are the light requirements for Stock?

Stock requires at least six hours of direct sunlight per day to thrive and produce abundant blooms. A south-facing window is ideal for indoor cultivation, providing the necessary intensity and duration of light. If natural light is insufficient, supplement with grow lights to ensure adequate illumination.

How do I care for Stock?

Stock thrives in full sun and well-draining soil. Water thoroughly when the top inch of soil feels dry, avoiding overwatering to prevent root rot. Fertilize every 2-3 weeks during the growing season with a balanced fertilizer, switching to a bloom-boosting fertilizer as buds form. Deadhead spent flowers regularly to encourage continuous blooming.

How do I propagate Stock?

Stock is primarily propagated by seed. Sow seeds indoors 6-8 weeks before the last frost or directly outdoors after the threat of frost has passed. Use a well-draining seed-starting mix. Keep the soil consistently moist but not waterlogged. Provide ample light and maintain a temperature of 65-70°F (18-21°C).

Last updated: April 29, 2026 — Plant care data reviewed and verified by our editorial team.