Flowering Onion vs New England Aster Plant Comparison

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

Flowering Onion

Flowering Onion

Allium spp.

VS
New England Aster

New England Aster

Symphyotrichum novae-angliae

Flowering Onion

Flowering Onion

Allium spp.

Flowering onions, or ornamental alliums, are bulbous perennials grown for their showy, spherical flower heads composed of numerous small, star-shaped flowers. They come in various sizes and colors, ranging from white and pink to purple and deep burgundy. Most are outdoor plants, thriving in gardens and borders. While some smaller varieties can be grown in containers, they are not ideally suited for indoor environments due to their high light requirements and dormancy needs. People grow them for their striking blooms, architectural interest, and ability to attract pollinators.

Amaryllidaceae Various species originate from different regions, including Europe, Asia, and North America.
✨ Features: Attracts pollinators, deer-resistant, long-lasting blooms.
📖 Read Complete Flowering Onion Guide
New England Aster

New England Aster

Symphyotrichum novae-angliae

The New England Aster is a robust, clump-forming perennial wildflower, typically reaching heights of 3-7 feet. It's characterized by its lance-shaped, clasping leaves and vibrant daisy-like flowers that bloom in late summer and fall. The flowers are typically purple or violet, with a yellow center disk. This plant is primarily an outdoor species, valued for its late-season color and its ability to attract pollinators like butterflies and bees. It's rarely grown indoors due to its high light requirements and size.

Asteraceae North America
✨ Features: Attracts butterflies and bees, provides late-season color, deer resistant.
📖 Read Complete New England Aster Guide

Quick Plant Comparison

Feature Flowering Onion New England Aster
Light Full sun (at least 6-8 hours of direct sunlight per day) Full sun (at least 6 hours of direct sunlight daily)
Watering Every 1-2 weeks during the growing season, less frequently during dormancy. Every 7-10 days outdoors, depending on rainfall and temperature. Container plants may need more frequent watering.
Humidity 40-60% 30-50%
Temperature 15-25°C 10-27°C
Care Level Expert Expert
Growth Rate Moderate Fast
Max Height Variable, depending on the species, but typically 30-150 cm outdoors. Indoors, expect smaller sizes if grown in containers. Rarely grown indoors, but if attempted, expect 1-2 feet in a large container.
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining soil, such as a mix of potting soil, sand, and perlite. Well-drained soil, loamy or sandy soil is ideal. Tolerates a range of soil types.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 10 minutes weekly during the growing season. 15 minutes weekly outdoors during growing season for watering and deadheading.

🔬 Botanical Information — Comparing These Plants

Flowering Onion

Scientific Name Allium spp.
Family Amaryllidaceae
Native To Various species originate from different regions, including Europe, Asia, and North America.
Also Known As Flowering Onion, Ornamental Onion, Allium
Leaves The leaves are typically linear or strap-shaped, often with a bluish-green hue. They emerge from the base of the plant and may wither as the plant flowers.
Flowers Flowering onions produce showy, spherical flower heads composed of numerous small, star-shaped flowers. The flowers come in various colors, including white, pink, purple, and burgundy. They rarely flower indoors due to light requirements.

New England Aster

Scientific Name Symphyotrichum novae-angliae
Family Asteraceae
Native To North America
Also Known As New England Aster, Michaelmas Daisy
Leaves Lance-shaped, clasping leaves that are typically 3-6 inches long and arranged alternately along the stems. The leaves are slightly rough to the touch and have a slightly hairy texture.
Flowers Rarely flowers indoors. Outdoors, it produces daisy-like flowers with purple or violet petals and a yellow central disk. Flowers are typically 1-2 inches in diameter and bloom in clusters at the ends of the stems.

📏 Size & Growth — Plant Comparison

Flowering Onion

Height Variable, depending on the species, but typically 30-150 cm outdoors. Indoors, expect smaller sizes if grown in containers.
Spread Variable, depending on the species, typically 15-30 cm. Some species can spread via bulb offsets.
Growth Rate Moderate
Growth Pattern Upright, with basal leaves emerging from the bulb and a tall flower stalk rising above the foliage. The flower heads are typically spherical and composed of numerous small flowers.

New England Aster

Height Rarely grown indoors, but if attempted, expect 1-2 feet in a large container.
Spread Spreads via rhizomes; can reach 2-4 feet wide outdoors. Indoors, expect a smaller spread but still requires a large container.
Growth Rate Fast
Growth Pattern Upright, clump-forming perennial with multiple stems arising from a central crown. It spreads via rhizomes, forming colonies over time.

🌱 Propagation — Comparing Plant Growth

Flowering Onion

Methods: Bulb offsets, Seed

Difficulty: Moderate

Tips: Separate bulb offsets from the main bulb in the fall and replant them. Sow seeds in the spring after a period of cold stratification.

New England Aster

Methods: Seed, Division, Stem cuttings

Difficulty: Easy

Tips: Divide clumps in spring or fall. Take stem cuttings in late spring or early summer. Sow seeds in fall or early spring.

✨ Benefits & Features — Comparing Plant Value

Flowering Onion

Flowering onions are known for their distinctive spherical flower heads, which can range in size from a golf ball to a softball. They offer a unique architectural element in the garden and attract beneficial insects.

  • ✓ Attracts pollinators to the garden
  • ✓ Deer-resistant, protecting other plants
  • ✓ Adds architectural interest with unique flower shapes
  • ✓ Provides long-lasting blooms for visual appeal
  • ✓ Low-maintenance once established
  • ⚠️ Toxic to pets

New England Aster

The New England Aster is known for its vibrant purple or violet flowers that bloom in late summer and fall, providing a crucial food source for pollinators when other flowers are fading. Its ability to thrive in a variety of soil conditions and its deer resistance make it a valuable addition to many gardens.

  • ✓ Attracts pollinators, supporting local ecosystems.
  • ✓ Provides late-season color, extending the garden's beauty.
  • ✓ Deer resistance reduces garden damage.
  • ✓ Relatively low maintenance once established.
  • ✓ Adds a natural, wild aesthetic to the garden.
  • 🐾 Pet Safe

📅 Maintenance Schedule — Plant Care Comparison

Flowering Onion

Repotting Not typically repotted if grown outdoors. If grown in containers, repot every 2-3 years in fresh soil.
Pruning Remove spent flower heads to prevent seed formation and encourage bulb growth. Cut back foliage after it has completely died back in the fall.
Fertilizing Balanced fertilizer (10-10-10) diluted to half strength, applied once in early spring and again after flowering.
Seasonal Care In spring, fertilize and water regularly as new growth emerges. In summer, enjoy the blooms. In fall, allow foliage to die back naturally and reduce watering. In winter, provide a dry, cool dormancy period.

New England Aster

Repotting Not typically grown indoors, but if in a container, repot every 1-2 years, or as needed if root-bound, especially given its rhizomatous nature.
Pruning Pinch back stems in late spring to promote bushier growth and more flowers. Deadhead spent flowers to encourage continued blooming.
Fertilizing Apply a balanced fertilizer (10-10-10) in early spring before new growth emerges. Avoid over-fertilizing, which can lead to leggy growth.
Seasonal Care In fall, cut back stems after flowering. In winter, mulch around the base of the plant for added protection. In spring, divide clumps if needed.

🌞 Light Requirements

Flowering Onion

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

Low light tolerant: ❌ No

New England Aster

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

Low light tolerant: ❌ No

💧 Watering Needs

Flowering Onion

Water thoroughly when the top inch of soil is dry. Avoid overwatering, which can lead to bulb rot. Reduce watering during dormancy. Signs of overwatering include yellowing leaves and a mushy bulb. Underwatering is indicated by wilting leaves and stunted growth.

New England Aster

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. In containers, ensure proper drainage. Signs of underwatering include wilting leaves, while overwatering can cause yellowing and mushy stems.

🌡️ Temperature & Humidity

Flowering Onion

Temperature: 15-25°C

Humidity: 40-60%

New England Aster

Temperature: 10-27°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Flowering Onion

Flowering Onion

Allium spp.
Care: Expert Time: 10 minutes weekly during the growing season. Beginner: No

Gardeners looking for striking, low-maintenance perennials to add architectural interest and attract pollinators to their outdoor spaces.

✅ Choose This Plant If...

  • You want a deer-resistant plant for your garden
  • You want to attract pollinators like bees and butterflies
  • You appreciate unique, globe-shaped flowers
  • You have a sunny garden space
  • You want a low-maintenance perennial that returns year after year

❌ 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: Outdoor garden beds, borders, or rock gardens with full sun exposure.
🎨 Style: Cottage, Naturalistic, Modern
🏠 Apartment Friendly: No
⚠️ All parts of the plant, especially the bulbs, contain organosulfides that can cause gastrointestinal upset, anemia, and damage to red blood cells in dogs, cats, and horses. Symptoms include vomiting, diarrhea, weakness, and loss of appetite.
New England Aster

New England Aster

Symphyotrichum novae-angliae
Care: Expert Time: 15 minutes weekly outdoors during growing season for watering and deadheading. Beginner: No

Gardeners looking for late-season color and pollinator-attracting plants in their outdoor gardens.

✅ Choose This Plant If...

  • You want to attract butterflies and bees to your garden.
  • You need a plant that provides late-season color.
  • You have a sunny garden spot with well-drained soil.
  • You want a relatively low-maintenance perennial.
  • You want a deer-resistant plant.

❌ Skip This Plant If...

  • You don't have a sunny outdoor location.
  • You are looking for an easy indoor plant.
  • You live in a very humid climate where powdery mildew is prevalent.
📍 Ideal Location: Outdoor garden, sunny border, wildflower meadow
🎨 Style: Cottage, Naturalistic, Wildflower
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, New England Asters are not toxic to dogs, cats, or horses.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly New England Aster ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

☀️

Flowering Onion needs full sun (at least 6-8 hours of direct sunlight per day), while New England Aster prefers full sun (at least 6 hours of direct sunlight daily).

📈

Flowering Onion has moderate growth, while New England Aster grows fast.

💡 Pro Tips For Comparing These Plants

Flowering Onion Care Tips

Flowering onions are primarily outdoor plants requiring full sun and well-draining soil. Indoor cultivation is challenging due to their high light needs and dormancy requirements. They are toxic to pets, so caution is needed if grown in areas accessible to animals. Regular watering and occasional fertilization are necessary for optimal growth.

  • Plant bulbs in well-draining soil to prevent rot
  • Provide full sun for optimal flowering
  • Water deeply but infrequently, allowing the soil to dry out between waterings
  • Fertilize in early spring and after flowering to promote bulb growth
  • Remove spent flower heads to encourage bulb development
❄️ Winter: Allow foliage to die back naturally. Provide a dry, cool dormancy period. Avoid overwatering.
☀️ Summer: Water regularly during dry periods. Provide support for tall flower stalks if needed. Monitor for pests and diseases.

New England Aster Care Tips

New England Asters are primarily outdoor plants and are challenging to grow indoors due to their high light requirements and tendency to spread. They need full sun and well-drained soil. Indoor attempts require supplemental lighting and careful monitoring of watering to prevent root rot. Expect limited flowering indoors.

  • Provide full sun for optimal flowering.
  • Ensure well-drained soil to prevent root rot.
  • Pinch back stems in late spring to promote bushier growth.
  • Divide clumps every few years to prevent overcrowding.
  • Monitor for powdery mildew and treat promptly.
❄️ Winter: Cut back stems to the ground after flowering has finished. Mulch around the base of the plant to protect the roots from freezing temperatures.
☀️ Summer: Water regularly during dry periods. Deadhead spent flowers to encourage continued blooming. Monitor for pests and diseases.

⚠️ Common Problems & Solutions — Plant Care Comparison

Flowering Onion

Common Issues: Bulb rot, Onion white rot, Allium leaf miner, Aphids
Solutions: Ensure well-draining soil and avoid overwatering to prevent bulb rot. Remove and destroy infected plants to control onion white rot. Use insecticidal soap to control allium leaf miner and aphids.

New England Aster

Common Issues: Powdery mildew, Aster yellows, Root rot
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. | Aster yellows: Remove and destroy infected plants. | Root rot: Ensure well-draining soil and avoid overwatering.

❓ Frequently Asked Questions — Comparing These Plants

Flowering Onion

What are the light requirements for Flowering Onion?

Flowering Onions need ample sunlight to produce vibrant blooms. Aim for at least 6 hours of direct sunlight per day. If growing indoors, place them near a south-facing window where they can receive the most sunlight. Insufficient light can result in weak stems, pale foliage, and a lack of flowers. If natural light is limited, supplement with grow lights to provide the necessary intensity. Rotate the plant regularly to ensure even light exposure on all sides. Consider using a light meter to measure the light intensity and adjust the plant’s position accordingly.

How do I care for Flowering Onion?

Flowering Onions thrive in well-draining soil and require full sun to partial shade for optimal growth and flowering. Water thoroughly when the top inch of soil feels dry, allowing excess water to drain away. Avoid overwatering, as this can lead to bulb rot. Fertilize during the growing season (spring and summer) with a balanced, slow-release fertilizer or a liquid feed diluted to half strength every 2-4 weeks to promote abundant blooms. Deadhead spent flowers to encourage further blooming and prevent seed production. Protect from frost in colder climates by mulching heavily or moving potted plants indoors. Repot every 2-3 years as needed, using a pot slightly larger than the previous one. Ensure good air circulation around the plants to prevent fungal diseases.

How do I propagate Flowering Onion?

Flowering Onions can be propagated through division, a relatively simple method. In the fall, after the foliage has died back, carefully dig up the bulbs. Separate the smaller bulblets from the main bulb. Replant the bulblets in well-draining soil, spacing them a few inches apart. Water thoroughly and mulch to protect them from frost. They may take a year or two to reach flowering size. Stem cuttings and keiki propagation are not applicable to Flowering Onions, as they are bulbous plants. Division is the primary method for increasing your stock of these beautiful plants. Ensure the bulblets have some roots attached for best results.

New England Aster

What are the light requirements for New England Aster?

New England Aster demands ample sunlight to produce its profuse blooms. Ideally, provide at least six hours of direct sunlight each day. A south-facing location is generally best, although east- or west-facing exposures can also work if they receive sufficient sunlight. Insufficient light can result in leggy growth, reduced flowering, and increased susceptibility to diseases. If growing indoors, supplement natural light with grow lights, especially during the shorter days of fall and winter. Rotate the plant regularly to ensure even light exposure. If the leaves start to turn pale or yellow, it may indicate that the plant is receiving too little light.

How do I care for New England Aster?

New England Aster thrives in full sun, requiring at least six hours of direct sunlight daily. Water regularly, especially during dry periods, ensuring the soil remains consistently moist but not waterlogged. Fertilize in early spring with a balanced fertilizer to promote healthy growth and abundant blooms. Pinch back stems in late spring or early summer to encourage bushier growth and more flowers. Deadhead spent blooms to prolong the flowering season. Divide established clumps every few years to prevent overcrowding and maintain vigor. Provide support, such as staking, if the plants become too tall or leggy. Monitor for pests and diseases, and treat promptly if necessary. Ensure good air circulation to prevent fungal diseases. Mulch around the base of the plant to retain moisture and suppress weeds.

How do I propagate New England Aster?

New England Asters can be easily propagated through division, stem cuttings, or seeds. For division, carefully dig up an established clump in early spring or fall and separate it into smaller sections, each with healthy roots and shoots. Replant the divisions in well-prepared soil. For stem cuttings, take 4-6 inch cuttings from new growth in spring or early summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cuttings in moist potting mix and keep them humid until roots develop. Seeds can be sown in early spring indoors or directly in the garden after the last frost. Ensure proper spacing for optimal growth.

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