Floss Flower vs Perennial Pea Plant Comparison

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

Floss Flower

Floss Flower

Ageratum houstonianum

VS
Perennial Pea

Perennial Pea

Lathyrus latifolius

Floss Flower

Floss Flower

Ageratum houstonianum

Ageratum houstonianum, commonly known as Floss Flower, is an annual flowering plant characterized by its fuzzy, pom-pom-like flower heads. It typically grows to a height of 6-18 inches. The flowers are most commonly blue, but cultivars are available in pink, white, and purple. It is primarily grown outdoors as a bedding plant or in containers for its long-lasting blooms and attractive appearance. While it can be attempted indoors, it requires very bright light and consistent care to thrive, making it more challenging than other indoor plants.

Asteraceae Central America, Mexico
✨ Features: Long blooming period, attractive to pollinators
📖 Read Complete Floss Flower Guide
Perennial Pea

Perennial Pea

Lathyrus latifolius

Lathyrus latifolius, commonly known as Perennial Pea, is a climbing perennial vine that can reach lengths of 6 feet or more. It features winged stems and tendrils that allow it to scramble over other plants or structures. The plant produces showy, pea-like flowers in shades of pink, rose, purple, and white during the summer months. While visually appealing, it's primarily an outdoor plant and not suited for indoor cultivation due to its need for full sun and extensive root system. People grow it for its attractive flowers and ability to cover fences or trellises.

Fabaceae Europe
✨ Features: Attractive flowers, ability to attract pollinators
📖 Read Complete Perennial Pea Guide

Quick Plant Comparison

Feature Floss Flower Perennial Pea
Light Full sun to partial shade outdoors. Indoors, requires very bright, direct light for at least 6 hours daily. Full sun (at least 6 hours of direct sunlight daily)
Watering Every 3-7 days outdoors, depending on weather. Every 5-10 days indoors, depending on light and humidity. Every 7-10 days, depending on weather conditions
Humidity 40-60% 30-50%
Temperature 18-24°C 15-25°C
Care Level Expert Expert
Growth Rate Moderate Fast
Max Height 6-18 inches (15-45 cm) indoors, potentially smaller N/A (Outdoor plant, not suitable for indoor growing)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining potting mix. A mix of peat moss, perlite, and vermiculite is suitable. Well-drained soil, loamy or sandy soil is preferred
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 10-15 minutes weekly 30 minutes weekly during growing season

🔬 Botanical Information — Comparing These Plants

Floss Flower

Scientific Name Ageratum houstonianum
Family Asteraceae
Native To Central America, Mexico
Also Known As Floss Flower, Blueweed, Mexican Ageratum
Leaves The leaves are oval to heart-shaped, with slightly serrated edges. They are typically medium green in color and have a slightly rough texture.
Flowers It flowers readily outdoors. Indoors, flowering is possible with sufficient light, but less reliable. The flowers are small, fuzzy, and clustered together in dense, pom-pom-like heads. They are most commonly blue, but cultivars are available in pink, white, and purple.

Perennial Pea

Scientific Name Lathyrus latifolius
Family Fabaceae
Native To Europe
Also Known As Perennial Pea, Everlasting Pea, Broad-leaved Everlasting Pea
Leaves The leaves are alternate, pinnately compound with two leaflets and a terminal tendril. The leaflets are lance-shaped, 5-10 cm long, and have a bluish-green color.
Flowers The flowers are pea-like, about 2-3 cm wide, and come in shades of pink, rose, purple, and white. They are borne in clusters on long stalks during the summer months. It will not flower indoors.

📏 Size & Growth — Plant Comparison

Floss Flower

Height 6-18 inches (15-45 cm) indoors, potentially smaller
Spread 6-12 inches (15-30 cm)
Growth Rate Moderate
Growth Pattern Bushy, compact growth habit. It typically grows upright, forming a mound of foliage and flowers.

Perennial Pea

Height N/A (Outdoor plant, not suitable for indoor growing)
Spread Spreads via rhizomes and seeds, can be aggressive
Growth Rate Fast
Growth Pattern Climbing vine that uses tendrils to attach to supports. It can grow several feet in a single season and spreads both by seed and rhizomes.

🌱 Propagation — Comparing Plant Growth

Floss Flower

Methods: Seed, Stem cuttings

Difficulty: Easy

Tips: For seeds, sow indoors 6-8 weeks before the last frost. For stem cuttings, take 4-6 inch cuttings in spring or summer and root in water or moist potting mix.

Perennial Pea

Methods: Seed, Division, Root cuttings

Difficulty: Easy

Tips: Soak seeds in warm water for 24 hours before planting to improve germination. Divide established plants in spring or fall. Root cuttings can be taken in late fall or early spring.

✨ Benefits & Features — Comparing Plant Value

Floss Flower

The fuzzy, pom-pom-like flower heads are unique and add a soft texture to the garden. The plant's long blooming period provides continuous color throughout the growing season. It is also attractive to pollinators, making it a beneficial addition to any garden.

  • ✓ Attracts pollinators
  • ✓ Adds vibrant color to the garden
  • ✓ Long blooming period
  • ✓ Relatively easy to propagate
  • ✓ Can be used in cut flower arrangements
  • ⚠️ Toxic to pets

Perennial Pea

The Perennial Pea is a long-lived perennial vine with showy flowers. Unlike some other pea species, it does not produce edible pods.

  • ✓ Attracts pollinators like bees and butterflies.
  • ✓ Provides beautiful vertical interest in the garden.
  • ✓ Relatively low maintenance once established.
  • ✓ Can help to stabilize soil on slopes.
  • ✓ Offers a long blooming period throughout the summer.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Floss Flower

Repotting Not typically repotted as it is an annual. If grown indoors, repot in spring if root-bound.
Pruning Deadhead spent flowers to encourage continued blooming.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-4 weeks during the growing season.
Seasonal Care In spring and summer, provide regular watering and fertilization. In fall, reduce watering as temperatures cool. In winter, the plant typically dies back as it is an annual.

Perennial Pea

Repotting N/A (Outdoor plant)
Pruning Prune regularly to control spread and remove dead or damaged foliage. Cut back hard in fall after flowering.
Fertilizing Balanced fertilizer (10-10-10) in spring, diluted to half strength. Avoid over-fertilizing.
Seasonal Care In spring, fertilize and provide support for climbing. In summer, water regularly and deadhead spent flowers. In fall, cut back foliage after flowering. In winter, allow the plant to rest.

🌞 Light Requirements

Floss Flower

Full sun to partial shade outdoors. Indoors, requires very bright, direct light for at least 6 hours daily.

Low light tolerant: ❌ No

Perennial Pea

Full sun (at least 6 hours of direct sunlight daily)

Low light tolerant: ❌ No

💧 Watering Needs

Floss Flower

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Ensure good drainage. Indoors, allow the soil to dry slightly between waterings. Signs of overwatering include yellowing leaves and wilting, while underwatering results in dry, crispy leaves.

Perennial Pea

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. During hot, dry periods, more frequent watering may be necessary. Allow the soil to drain well after watering.

🌡️ Temperature & Humidity

Floss Flower

Temperature: 18-24°C

Humidity: 40-60%

Perennial Pea

Temperature: 15-25°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Floss Flower

Floss Flower

Ageratum houstonianum
Care: Expert Time: 10-15 minutes weekly Beginner: No

Experienced gardeners who want a colorful, long-blooming annual for outdoor beds and containers, and are aware of the toxicity to pets.

✅ Choose This Plant If...

  • You want a long-blooming annual for your garden.
  • You need a plant that attracts butterflies and bees.
  • You have a sunny outdoor space.
  • You are experienced with plant care and can provide the necessary conditions.
  • You are looking for a plant with a unique, fuzzy flower texture.

❌ Skip This Plant If...

  • You have pets that may ingest the plant.
  • You cannot provide full sun or very bright light.
  • You are a beginner gardener.
  • You prefer low-maintenance plants.
  • You are looking for a plant that thrives indoors.
📍 Ideal Location: Outdoors: Sunny garden bed or container. Indoors: South-facing window with direct sunlight.
🎨 Style: Cottage, Traditional, Bohemian
🏠 Apartment Friendly: Limited
⚠️ According to the ASPCA, Ageratum houstonianum contains pyrrolizidine alkaloids, which are toxic to dogs, cats, and horses. Symptoms include liver damage, vomiting, diarrhea, and abdominal pain. All parts of the plant are considered toxic.
Perennial Pea

Perennial Pea

Lathyrus latifolius
Care: Expert Time: 30 minutes weekly during growing season Beginner: No

Gardeners looking for a flowering vine to cover fences, trellises, or walls in a sunny location.

✅ Choose This Plant If...

  • You want a fast-growing vine to cover a fence or trellis.
  • You have a sunny garden and want to attract pollinators.
  • You enjoy the look of pea-like flowers in various colors.
  • You are looking for a low-maintenance perennial once established.
  • You want a plant that can tolerate a wide range of soil conditions.

❌ Skip This Plant If...

  • You have pets or small children who might ingest the plant.
  • You have a small garden and are concerned about aggressive spreading.
  • You are looking for an indoor plant.
  • You don't have a location with full sun.
  • You are sensitive to plants that may cause skin irritation.
📍 Ideal Location: Outdoor garden, fence, trellis, or wall in a sunny location.
🎨 Style: Cottage, Traditional, Romantic
🏠 Apartment Friendly: No
⚠️ The seeds of Lathyrus species contain lathyrogens, which are toxic to animals including dogs, cats, and horses. Symptoms include neurological issues, weakness, and paralysis. All parts of the plant should be considered 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

📈

Floss Flower has moderate growth, while Perennial Pea grows fast.

💡 Pro Tips For Comparing These Plants

Floss Flower Care Tips

Floss Flower is primarily an outdoor plant that requires full sun and well-drained soil. Indoor cultivation is challenging due to its high light requirements. It needs consistent watering and fertilization. Toxicity to pets is a significant concern.

  • Provide well-draining soil to prevent root rot.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Fertilize every 2-4 weeks during the growing season.
  • Protect from strong winds.
  • Monitor for pests and diseases and treat promptly.
❄️ Winter: As an annual, it typically dies back in winter. Remove dead foliage and discard the plant.
☀️ Summer: Provide regular watering and fertilization during the summer growing season. Deadhead spent flowers to encourage continued blooming. Protect from intense afternoon sun in very hot climates.

Perennial Pea Care Tips

Perennial Pea is an outdoor plant that requires full sun and well-drained soil. It is not suitable for indoor growing due to its light and space requirements. It can be an aggressive spreader, so containment may be necessary. Toxicity to pets is a significant concern.

  • Provide a sturdy support structure for the vine to climb.
  • Deadhead spent flowers to encourage continued blooming.
  • Monitor for signs of powdery mildew and treat promptly.
  • Control spread by pruning and removing unwanted seedlings.
  • Avoid planting near areas where pets or children have access.
❄️ Winter: Cut back the foliage to the ground in late fall or early winter. The plant will go dormant and re-emerge in the spring.
☀️ Summer: Water regularly during dry periods. Deadhead spent flowers to encourage continued blooming. Monitor for pests and diseases.

⚠️ Common Problems & Solutions — Plant Care Comparison

Floss Flower

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

Perennial Pea

Common Issues: Powdery mildew, Aphids, Overgrowth
Solutions: Powdery mildew: Improve air circulation and apply fungicide. Aphids: Insecticidal soap or neem oil. Overgrowth: Prune regularly to control spread.

❓ Frequently Asked Questions — Comparing These Plants

Floss Flower

What are the light requirements for Floss Flower?

Floss Flower requires at least six hours of direct sunlight per day to thrive and produce abundant blooms. A sunny south-facing window is ideal for indoor cultivation. If natural light is insufficient, supplement with grow lights. Insufficient light can lead to leggy growth and reduced flowering. Rotate the plant regularly to ensure even light exposure on all sides. Avoid placing the plant in overly shaded areas, as this can weaken the plant and make it more susceptible to diseases. Early morning sun is preferable to harsh afternoon sun, especially in hot climates.

How do I care for Floss Flower?

Floss Flower thrives in well-draining soil and prefers a sunny location, although it can tolerate partial shade. Water regularly, especially during hot, dry periods, keeping the soil consistently moist but not waterlogged. Fertilize every 2-3 weeks during the growing season with a balanced liquid fertilizer to promote abundant blooms. Deadhead spent flowers regularly to encourage continuous flowering. Prune back leggy growth to maintain a compact shape. Protect from frost and freezing temperatures, as Floss Flower is sensitive to cold. Indoors, ensure adequate air circulation to prevent fungal diseases. Monitor for pests like aphids and spider mites and treat promptly. Repotting is generally not necessary for annual varieties, but container-grown perennials may benefit from repotting every 1-2 years.

How do I propagate Floss Flower?

Floss Flower is easily propagated by seeds. Sow seeds directly into the garden in spring after the last frost or start indoors 6-8 weeks earlier. For stem cuttings, take 4-6 inch cuttings from healthy stems, remove the lower leaves, and place in water or moist potting mix until roots develop. Division is possible for perennial varieties. Carefully dig up the plant and separate the root ball into smaller sections, ensuring each section has healthy roots and foliage. Replant the divisions in fresh soil. Keiki propagation is not applicable to Floss Flower.

Perennial Pea

What are the light requirements for Perennial Pea?

Perennial Pea requires at least 6-8 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. In hotter climates, some afternoon shade can be beneficial to prevent scorching of the leaves and flowers. Insufficient light can lead to leggy growth, reduced flowering, and pale foliage. If growing indoors, supplement with grow lights if natural light is limited. Rotate the plant regularly to ensure even light exposure on all sides. Monitor your Perennial Pea closely and adjust its location as needed to ensure it receives adequate sunlight.

How do I care for Perennial Pea?

Perennial Pea thrives in full sun to partial shade and requires well-drained soil. Water regularly, especially during dry periods, but avoid overwatering, which can lead to root rot. Fertilize in spring with a balanced fertilizer to promote healthy growth and abundant blooms. Deadhead spent flowers to encourage continued flowering throughout the season. Provide a sturdy support structure, such as a trellis or fence, for the plant to climb. Prune back in late fall or early spring to control its size and shape. Watch out for common pests like aphids and spider mites, and treat infestations promptly. Mulch around the base of the plant to retain moisture and suppress weeds. Regular monitoring and preventative measures are key to keeping your Perennial Pea healthy and vibrant.

How do I propagate Perennial Pea?

Perennial Pea can be propagated by seed, division, or stem cuttings. For seed propagation, scarify the seeds and soak them in water for 24 hours before planting. Sow seeds indoors in early spring or directly outdoors after the last frost. For division, carefully dig up a mature plant in early spring or late fall and divide the root ball into smaller sections, each with its own set of roots and shoots. Replant the divisions in well-draining soil. For stem cuttings, take 4-6 inch cuttings from healthy stems in late spring or early summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cuttings in a well-draining potting mix and keep them moist until they root.

Last updated: May 12, 2026 — Plant care data reviewed and verified by our editorial team.