Cosmos vs Hummingbird Mint Plant Comparison

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

Cosmos

Cosmos

Cosmos bipinnatus

VS
Hummingbird Mint

Hummingbird Mint

Agastache spp.

Cosmos

Cosmos

Cosmos bipinnatus

Cosmos bipinnatus is an annual flowering plant typically grown outdoors. It features delicate, fern-like foliage and daisy-like flowers in shades of pink, purple, white, and occasionally yellow or orange. Plants typically reach heights of 1 to 6 feet. Cosmos are popular for their long blooming season, attracting pollinators like bees and butterflies. They are primarily grown for ornamental purposes in gardens and meadows, adding color and texture to landscapes. While relatively easy to grow outdoors, they are not well-suited for indoor cultivation due to their high light requirements and large size.

Asteraceae Mexico
✨ Features: Attracts pollinators, long blooming season, cut flowers
📖 Read Complete Cosmos Guide
Hummingbird Mint

Hummingbird Mint

Agastache spp.

Agastache, commonly known as Hummingbird Mint, is a genus of herbaceous perennial plants known for their aromatic foliage and vibrant, nectar-rich flowers. They typically grow between 1 to 5 feet tall, forming bushy clumps. The leaves are usually lance-shaped and toothed. The flowers, which bloom from summer to fall, come in a variety of colors, including purple, pink, orange, and red. Agastache is primarily an outdoor plant, valued for attracting pollinators like hummingbirds and bees to gardens. People grow it for its ornamental value, drought tolerance, and fragrant foliage.

Lamiaceae North America and Asia, depending on species
✨ Features: Attracts hummingbirds and bees, aromatic foliage, drought tolerant
📖 Read Complete Hummingbird Mint Guide

Quick Plant Comparison

Feature Cosmos Hummingbird Mint
Light Full sun (at least 6-8 hours of direct sunlight daily) Full sun (at least 6 hours of direct sunlight daily)
Watering Every 1-2 weeks, depending on weather and soil drainage Every 7-10 days, depending on weather and soil drainage
Humidity 30-50% 30-50%
Temperature 18-27°C 18-30°C
Care Level Expert Expert
Growth Rate Fast Moderate To Fast
Max Height N/A (Outdoor plant, unsuitable for indoor growing) 0.3-1 meter (indoors, unlikely to thrive)
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil Well-draining soil; sandy or loamy soil is ideal Well-draining soil, such as a sandy or loamy mix. Avoid heavy clay soils.
Beginner Friendly ✅ Yes ❌ No
Weekly Maintenance 5 minutes weekly 10-15 minutes weekly (outdoor)

🔬 Botanical Information — Comparing These Plants

Cosmos

Scientific Name Cosmos bipinnatus
Family Asteraceae
Native To Mexico
Also Known As Cosmos, Garden Cosmos, Mexican Aster
Leaves The leaves of Cosmos bipinnatus are finely divided and fern-like, giving the plant a delicate and airy appearance. They are typically green in color and arranged oppositely along the stems. The leaves are relatively small, adding to the plant's overall graceful form.
Flowers Cosmos rarely, if ever, flower indoors due to insufficient light. Outdoors, they produce daisy-like flowers with a central disc and ray florets in shades of pink, purple, white, and occasionally yellow or orange. The flowers are typically 2-4 inches in diameter and bloom profusely throughout the summer and fall.

Hummingbird Mint

Scientific Name Agastache spp.
Family Lamiaceae
Native To North America and Asia, depending on species
Also Known As Hummingbird Mint, Anise Hyssop, Giant Hyssop
Leaves The leaves are typically lance-shaped to ovate, with toothed edges. They are usually green or gray-green in color and have a distinct aromatic scent when crushed. The texture can range from smooth to slightly hairy, depending on the species.
Flowers Agastache rarely flowers indoors. Outdoors, it produces abundant flower spikes from summer to fall. The flowers are tubular and come in a variety of colors, including purple, pink, orange, red, and white. They are highly attractive to hummingbirds and bees.

📏 Size & Growth — Plant Comparison

Cosmos

Height N/A (Outdoor plant, unsuitable for indoor growing)
Spread N/A (Outdoor plant, unsuitable for indoor growing)
Growth Rate Fast
Growth Pattern Cosmos grow upright with branching stems. They can reach heights of 1 to 6 feet, depending on the variety. The plants produce numerous flowers on long stems, making them excellent for cutting.

Hummingbird Mint

Height 0.3-1 meter (indoors, unlikely to thrive)
Spread 0.3-0.6 meter (can spread via rhizomes, depending on species)
Growth Rate Moderate To Fast
Growth Pattern Agastache typically grows in an upright, bushy habit, forming clumps of foliage and flower spikes. Some species can spread via rhizomes, creating larger colonies over time.

🌱 Propagation — Comparing Plant Growth

Cosmos

Methods: Seed

Difficulty: Easy

Tips: Sow seeds directly into the garden after the last frost or start indoors 4-6 weeks before the last frost. Lightly cover seeds with soil and keep moist until germination.

Hummingbird Mint

Methods: Seed, stem cuttings, division

Difficulty: Easy To Moderate

Tips: For stem cuttings, take cuttings in spring or early summer and root them in water or well-draining soil. Division is best done in spring or fall.

✨ Benefits & Features — Comparing Plant Value

Cosmos

Cosmos are known for their delicate, fern-like foliage and daisy-like flowers that come in a variety of colors. They are also highly attractive to pollinators, making them a valuable addition to any garden. Their long blooming season provides continuous color throughout the summer and fall.

  • ✓ Attracts pollinators to your garden.
  • ✓ Provides beautiful cut flowers.
  • ✓ Adds vibrant color to your outdoor space.
  • ✓ Easy to grow and maintain.
  • ✓ Supports local ecosystems.
  • 🐾 Pet Safe

Hummingbird Mint

Agastache is known for its strong aromatic foliage and its ability to attract hummingbirds and other pollinators. The flowers come in a wide range of colors, making it a versatile addition to any garden. Its drought tolerance makes it suitable for xeriscaping.

  • ✓ Attracts pollinators, improving garden biodiversity.
  • ✓ Provides fragrant foliage for sensory enjoyment.
  • ✓ Drought-tolerant, reducing water consumption.
  • ✓ Adds vibrant color to the garden.
  • ✓ Some species have medicinal properties.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Cosmos

Repotting N/A (Outdoor plant)
Pruning Deadheading spent flowers
Fertilizing Balanced fertilizer (10-10-10) at half strength every 4-6 weeks during the growing season
Seasonal Care Deadhead spent flowers to encourage continued blooming. In colder climates, cosmos are grown as annuals and will die with the first frost.

Hummingbird Mint

Repotting Not applicable for outdoor plants. If grown in containers, repot every 1-2 years, or more frequently if root-bound.
Pruning Deadhead spent flowers to encourage continued blooming. Prune back in late fall or early spring.
Fertilizing Balanced slow-release fertilizer in spring. Avoid over-fertilizing.
Seasonal Care In winter, cut back the plant to the ground after the first frost. In spring, fertilize and provide support if needed. Summer requires regular watering during dry spells.

🌞 Light Requirements

Cosmos

Full sun (at least 6-8 hours of direct sunlight daily)

Low light tolerant: ❌ No

Hummingbird Mint

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

Low light tolerant: ❌ No

💧 Watering Needs

Cosmos

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Cosmos are relatively drought-tolerant once established. Signs of underwatering include wilting and drooping leaves. Overwatering can cause yellowing leaves and stem rot.

Hummingbird Mint

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, as this can lead to root rot. Signs of underwatering include wilting leaves, while overwatering can cause yellowing leaves and a soggy soil.

🌡️ Temperature & Humidity

Cosmos

Temperature: 18-27°C

Humidity: 30-50%

Hummingbird Mint

Temperature: 18-30°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Cosmos

Cosmos

Cosmos bipinnatus
Care: Expert Time: 5 minutes weekly Beginner: Yes

Gardeners looking for easy-to-grow, colorful annuals that attract pollinators.

✅ Choose This Plant If...

  • You want a low-maintenance plant for your garden.
  • You want to attract butterflies and bees to your yard.
  • You need a plant that blooms for a long period.
  • You want to add vibrant colors to your outdoor space.
  • You want easy-to-grow cut flowers.

❌ Skip This Plant If...

  • You don't have a sunny outdoor space.
  • You want a plant that thrives indoors.
  • You live in a very cold climate with a short growing season.
📍 Ideal Location: Outdoor garden, meadow, or container garden in a sunny location
🎨 Style: Cottage, Bohemian, Naturalistic
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Cosmos bipinnatus is not toxic to dogs, cats, or horses.
Hummingbird Mint

Hummingbird Mint

Agastache spp.
Care: Expert Time: 10-15 minutes weekly (outdoor) Beginner: No

Experienced gardeners who want to attract pollinators to their outdoor gardens.

✅ 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 appreciate fragrant foliage and colorful flowers.
  • You want a low-maintenance perennial for your garden.
  • You enjoy using herbs in teas or cooking (some species).

❌ Skip This Plant If...

  • You have limited sunlight in your home.
  • You are looking for an easy-to-grow indoor plant.
  • You have pets that might ingest the plant.
📍 Ideal Location: Outdoor garden, sunny border, or container garden in a sunny location.
🎨 Style: Cottage, Naturalistic, Mediterranean
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, plants in the mint family (Lamiaceae) contain essential oils that can cause gastrointestinal upset and dermatitis in dogs, cats, and horses. Symptoms include vomiting, diarrhea, weakness, and skin irritation. The specific toxic compounds vary by species.

🎯 Quick Verdict

Best for Beginners Cosmos
Pet Friendly Cosmos ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

☀️

Cosmos needs full sun (at least 6-8 hours of direct sunlight daily), while Hummingbird Mint prefers full sun (at least 6 hours of direct sunlight daily).

📈

Cosmos has fast growth, while Hummingbird Mint grows moderate to fast.

💡 Pro Tips For Comparing These Plants

Cosmos Care Tips

Cosmos are easy to grow outdoors in full sun and well-draining soil. They are not suitable for indoor growing due to their high light requirements and large size. Attempting to grow them indoors will likely result in leggy, weak plants with few flowers.

  • Deadhead spent flowers regularly to encourage more blooms.
  • Provide support for taller varieties to prevent them from flopping over.
  • Water deeply but infrequently, allowing the soil to dry out slightly between waterings.
  • Avoid over-fertilizing, as this can lead to excessive foliage growth and fewer flowers.
  • Plant in well-draining soil to prevent root rot.
❄️ Winter: Cosmos are annuals and do not survive winter in cold climates. Remove dead plants after the first frost.
☀️ Summer: Water regularly during hot, dry periods. Deadhead spent flowers to encourage continued blooming. Provide support for taller varieties to prevent them from flopping over in strong winds.

Hummingbird Mint Care Tips

Hummingbird Mint is primarily an outdoor plant and requires full sun to thrive. Growing it indoors is challenging due to its high light requirements and potential for pest infestations. It needs well-draining soil and careful watering to prevent root rot. Indoor growth is often stunted and flowering is unlikely.

  • Plant in well-draining soil to prevent root rot.
  • Provide full sun for optimal flowering.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Water deeply but infrequently, allowing the soil to dry out between waterings.
  • Protect from strong winds, especially taller varieties.
❄️ Winter: In colder climates, cut back the plant to the ground after the first frost. A layer of mulch can help protect the roots from freezing temperatures. Reduce watering significantly during dormancy.
☀️ Summer: Provide regular watering during dry spells. Deadhead spent flowers to encourage continued blooming. Monitor for pests and diseases, and treat as needed. Provide support for taller varieties to prevent them from flopping over.

⚠️ Common Problems & Solutions — Plant Care Comparison

Cosmos

Common Issues: Powdery mildew, aphids, stem rot
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Aphids: Spray with insecticidal soap or neem oil. Stem rot: Avoid overwatering and ensure good drainage.

Hummingbird Mint

Common Issues: Root rot, powdery mildew, spider mites, aphids
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Powdery mildew: Improve air circulation and apply a fungicide. Spider mites/Aphids: Insecticidal soap or neem oil.

❓ Frequently Asked Questions — Comparing These Plants

Cosmos

What are the light requirements for Cosmos?

Cosmos require a minimum of six to eight hours of direct sunlight per day to thrive and produce abundant blooms. Insufficient sunlight can result in leggy growth, weak stems, and reduced flowering. Choose a sunny location in your garden or on your balcony where the plants will receive ample sunlight throughout the day. If growing Cosmos indoors, place them near a south-facing window that provides the brightest light. Rotate the plants regularly to ensure even exposure to sunlight on all sides. If natural light is insufficient, supplement with grow lights to provide the necessary light intensity.

How do I care for Cosmos?

Cosmos thrive in full sun and well-draining soil. Water regularly, especially during dry periods, but avoid overwatering to prevent root rot. Fertilize lightly every few weeks with a balanced fertilizer, or a bloom-boosting formula during the flowering season, to encourage abundant blooms. Deadhead spent flowers regularly to promote continuous blooming. Cosmos are generally low-maintenance plants, but they may benefit from staking if they become tall and leggy. Prune them lightly to maintain their shape and encourage bushier growth. Protect them from strong winds, which can damage the delicate stems. Monitor for pests like aphids and treat them promptly if detected. Cosmos are generally annuals, but they may self-seed in some climates.

How do I propagate Cosmos?

Cosmos are most commonly propagated by seed. Sow seeds directly into the garden in spring after the last frost, or start them indoors 6-8 weeks earlier. For division, carefully dig up the plant in early spring or fall and separate the root ball into smaller clumps, ensuring each clump has healthy roots and foliage. Replant the divisions immediately in well-draining soil. Stem cuttings are not a common method for Cosmos, but can be attempted by taking 4-6 inch cuttings from new growth in spring, dipping them in rooting hormone, and planting them in moist potting mix. Keiki propagation is not applicable to Cosmos.

Hummingbird Mint

What are the light requirements for Hummingbird Mint?

Hummingbird Mint requires at least six hours of direct sunlight per day to thrive. Choose a location in your garden or on your patio that receives full sun exposure. If growing indoors, place the plant near a sunny window, preferably one facing south or west. Insufficient light can result in weak growth, fewer blooms, and leggy stems. If your plant is not getting enough natural light, consider supplementing with a grow light. Rotate the plant regularly to ensure even light exposure on all sides.

How do I care for Hummingbird Mint?

Hummingbird Mint thrives in full sun and well-draining soil. Water deeply but infrequently, allowing the soil to dry out between waterings. Avoid overwatering, which can lead to root rot. Fertilize lightly in spring with a balanced fertilizer to promote healthy growth and abundant blooms. Deadhead spent flowers regularly to encourage continuous blooming throughout the summer and fall. Prune back the plant in late winter or early spring to remove dead or damaged growth and maintain its shape. Provide good air circulation to prevent fungal diseases. In colder climates, provide winter protection by mulching around the base of the plant.

How do I propagate Hummingbird Mint?

Hummingbird Mint can be propagated through division, stem cuttings, or seed. For division, carefully dig up the plant in spring or fall and divide the root ball into smaller sections, each with healthy roots and shoots. Replant the divisions in well-draining soil. For stem cuttings, take 4-6 inch cuttings from new growth in spring or 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. Seeds can be sown indoors in early spring or directly outdoors after the last frost.

Last updated: May 1, 2026 — Plant care data reviewed and verified by our editorial team.