Bachelor's Button vs Flowering Kale Plant Comparison

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

Bachelor's Button

Bachelor's Button

Centaurea cyanus

VS
Flowering Kale

Flowering Kale

Brassica oleracea var. acephala

Bachelor's Button

Bachelor's Button

Centaurea cyanus

Bachelor's Button, or Cornflower, is an annual plant typically grown outdoors for its vibrant blue, pink, white, or purple flowers. It features slender, grey-green leaves and an upright growth habit, reaching heights of 1 to 3 feet. While admired for its ornamental value and use in cut flower arrangements, it is primarily an outdoor plant that thrives in full sun. People grow it for its attractive flowers that attract pollinators and its ease of cultivation in gardens and fields.

Asteraceae Europe, though naturalized in many parts of the world
✨ Features: Attracts pollinators such as bees and butterflies.
📖 Read Complete Bachelor's Button Guide
Flowering Kale

Flowering Kale

Brassica oleracea var. acephala

Flowering kale is a cool-season biennial grown as an annual for its vibrant, colorful foliage. It is not grown for edible leaves like its close relative, edible kale. The plant forms a rosette of ruffled or frilly leaves in shades of white, pink, purple, or red, surrounded by outer green leaves. It is primarily an outdoor plant, thriving in cooler temperatures and full sun. People grow it for its ornamental value, adding color and texture to gardens and containers during the fall and winter months.

Brassicaceae Europe
✨ Features: Provides vibrant color in cool-season gardens.
📖 Read Complete Flowering Kale Guide

Quick Plant Comparison

Feature Bachelor's Button Flowering Kale
Light Full sun (at least 6 hours of direct sunlight daily) Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal color development.
Watering Every 7-10 days, depending on weather and soil drainage Every 3-7 days, depending on weather and soil drainage.
Humidity 30-50% 40-60%
Temperature 15-24°C 4-18°C
Care Level Expert Expert
Growth Rate Fast Moderate
Max Height Not typically grown indoors; outdoors 30-90 cm 20-40 cm
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining soil, sandy or loamy soil is ideal Well-draining potting mix or garden soil enriched with organic matter.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 5 minutes weekly (deadheading, watering) 5 minutes weekly

🔬 Botanical Information — Comparing These Plants

Bachelor's Button

Scientific Name Centaurea cyanus
Family Asteraceae
Native To Europe, though naturalized in many parts of the world
Also Known As Cornflower, Bluebottle, Boutonniere Flower
Leaves The leaves are slender, lance-shaped, and grey-green in color. They are typically 2-5 cm long and have a slightly hairy texture.
Flowers It rarely flowers indoors. Outdoors, it produces vibrant blue, pink, white, or purple flowers. The flowers are typically 2-4 cm in diameter and have a fringed appearance.

Flowering Kale

Scientific Name Brassica oleracea var. acephala
Family Brassicaceae
Native To Europe
Also Known As Flowering Kale, Ornamental Kale, Ornamental Cabbage
Leaves The leaves of flowering kale are broad and ruffled or frilly, depending on the variety. They can range in size from 15-30 cm in diameter. The outer leaves are typically green, while the inner leaves display vibrant colors such as white, pink, purple, or red. The texture is often slightly waxy.
Flowers Flowering kale may produce small yellow flowers if it overwinters and bolts in the spring. However, it is primarily grown for its foliage, and the flowers are not particularly showy. Flowering is often considered undesirable as it signals the end of the plant's ornamental display.

📏 Size & Growth — Plant Comparison

Bachelor's Button

Height Not typically grown indoors; outdoors 30-90 cm
Spread Outdoors 30-60 cm
Growth Rate Fast
Growth Pattern Upright, branching annual plant. It grows from seed to flower in a single season, reaching a height of 1 to 3 feet. It does not spread aggressively but can self-seed readily.

Flowering Kale

Height 20-40 cm
Spread 20-40 cm
Growth Rate Moderate
Growth Pattern Flowering kale grows in a rosette shape, with tightly packed leaves forming a dense head. The outer leaves are typically green, while the inner leaves display vibrant colors like white, pink, purple, or red. It does not spread aggressively.

🌱 Propagation — Comparing Plant Growth

Bachelor's Button

Methods: Seed

Difficulty: Easy

Tips: Sow seeds directly into the garden in early spring or fall. Seeds need light to germinate, so do not cover them too deeply. Keep the soil moist until germination occurs.

Flowering Kale

Methods: Seed

Difficulty: Easy

Tips: Sow seeds indoors 6-8 weeks before the last expected frost or directly outdoors in late summer for fall/winter color. Provide consistent moisture and light for germination.

✨ Benefits & Features — Comparing Plant Value

Bachelor's Button

Bachelor's Button is known for its vibrant blue flowers, although other colors are available. It is an annual plant that readily self-seeds, making it a reliable addition to the garden year after year. It is also attractive to pollinators, making it a valuable plant for supporting local ecosystems.

  • ✓ Attracts pollinators to the garden
  • ✓ Provides beautiful cut flowers
  • ✓ Edible flowers for culinary use
  • ✓ Adds vibrant color to outdoor spaces
  • ✓ Easy to grow from seed outdoors
  • ⚠️ Toxic to pets

Flowering Kale

Flowering kale is unique for its vibrant colors that intensify in cool weather, providing ornamental value during the fall and winter months when many other plants are dormant. Unlike edible kale, it is primarily grown for its visual appeal rather than its flavor.

  • ✓ Adds vibrant color to cool-season gardens
  • ✓ Provides visual interest during the dormant season
  • ✓ Attracts beneficial insects
  • ✓ Easy to grow outdoors in suitable climates
  • ✓ Offers a unique textural element to garden designs
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Bachelor's Button

Repotting Not applicable as it is an annual plant typically grown directly in the ground.
Pruning Deadhead spent flowers to encourage more blooms and prevent seed formation if desired.
Fertilizing Balanced liquid fertilizer diluted to half strength, applied every 4-6 weeks during the growing season
Seasonal Care In spring, sow seeds directly into the garden. In summer, provide regular watering and deadhead spent flowers to encourage more blooms. In fall, collect seeds for next year's planting. In winter, the plant dies back as it is an annual.

Flowering Kale

Repotting Not typically repotted as it is grown as an annual.
Pruning Remove yellowing or damaged leaves to maintain appearance.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-4 weeks during the growing season.
Seasonal Care In fall and winter, provide protection from frost if temperatures drop below freezing. In spring, plants may bolt as temperatures rise. Remove spent flower stalks to encourage continued foliage production.

🌞 Light Requirements

Bachelor's Button

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

Low light tolerant: ❌ No

Flowering Kale

Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal color development.

Low light tolerant: ❌ No

💧 Watering Needs

Bachelor's Button

Water thoroughly when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. In well-draining soil, water deeply but infrequently. Signs of underwatering include wilting and dry, crispy leaves. Overwatering symptoms include yellowing leaves and a soggy soil.

Flowering Kale

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 soggy soil. Underwatering is indicated by wilting leaves.

🌡️ Temperature & Humidity

Bachelor's Button

Temperature: 15-24°C

Humidity: 30-50%

Flowering Kale

Temperature: 4-18°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Bachelor's Button

Bachelor's Button

Centaurea cyanus
Care: Expert Time: 5 minutes weekly (deadheading, watering) Beginner: No

Gardeners who want to attract pollinators to their outdoor gardens.

✅ Choose This Plant If...

  • You want to attract pollinators to your garden.
  • You enjoy cut flowers and want to grow your own.
  • You want a low-maintenance annual for a sunny spot.
  • You want to add a splash of vibrant color to your garden.
  • You enjoy edible flowers in salads or teas.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You don't have a sunny outdoor space.
  • You are looking for a low-maintenance indoor plant.
📍 Ideal Location: Outdoor garden, flower bed, or meadow in full sun
🎨 Style: Cottage garden, wildflower meadow, traditional
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Centaurea cyanus is toxic to dogs, cats, and horses. Symptoms include dermatitis and gastrointestinal upset. All parts of the plant are considered toxic.
Flowering Kale

Flowering Kale

Brassica oleracea var. acephala
Care: Expert Time: 5 minutes weekly Beginner: No

Gardeners looking to add vibrant color to their fall and winter gardens.

✅ Choose This Plant If...

  • You want vibrant fall and winter color in your garden.
  • You have a sunny outdoor space with cool temperatures.
  • You enjoy container gardening with seasonal plants.
  • You want a low-maintenance plant for outdoor displays.
  • You appreciate the unique texture and form of ornamental foliage.

❌ Skip This Plant If...

  • You have limited sunlight indoors.
  • You live in a consistently warm climate.
  • You have pets that might ingest the plant.
  • You are looking for a long-term indoor houseplant.
📍 Ideal Location: Outdoor gardens, patios, balconies, or decks with full sun exposure.
🎨 Style: Cottage, Rustic, Fall, Winter
🏠 Apartment Friendly: Limited
⚠️ All parts of the plant are considered mildly toxic to dogs, cats, and horses. Symptoms include gastrointestinal upset, such as vomiting and diarrhea. The ASPCA lists Brassica oleracea as containing glucosinolates, which can cause irritation.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Neither - caution
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

📈

Bachelor's Button has fast growth, while Flowering Kale grows moderate.

💡 Pro Tips For Comparing These Plants

Bachelor's Button Care Tips

Bachelor's Button 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 cultivation requires supplemental lighting and careful watering to prevent fungal diseases. It is best suited for outdoor gardens.

  • Sow seeds directly in the garden in early spring or fall.
  • Choose a location with full sun and well-draining soil.
  • Water regularly, especially during dry periods.
  • Deadhead spent flowers to encourage more blooms.
  • Protect from strong winds.
❄️ Winter: As an annual, Bachelor's Button dies back in the winter. Collect seeds for planting in the spring.
☀️ Summer: Provide regular watering during hot, dry periods. Deadhead spent flowers to encourage more blooms. Protect from strong winds.

Flowering Kale Care Tips

Flowering kale is primarily an outdoor plant and requires full sun and cool temperatures to thrive. It is challenging to maintain indoors due to its high light requirements and sensitivity to warm, dry air. Indoor plants often become leggy and lose their color.

  • Plant in well-draining soil to prevent root rot.
  • Provide at least 6 hours of direct sunlight daily for best color.
  • Water regularly, but avoid overwatering.
  • Fertilize every 2-4 weeks with a balanced liquid fertilizer.
  • Protect from extreme cold or frost if necessary.
❄️ Winter: Protect from extreme cold or frost by covering with a blanket or moving to a sheltered location. Reduce watering frequency during colder periods. Ensure adequate sunlight exposure.
☀️ Summer: Flowering kale typically does not thrive in hot summer temperatures. Provide shade during the hottest part of the day to prevent bolting. Ensure adequate watering to prevent stress.

⚠️ Common Problems & Solutions — Plant Care Comparison

Bachelor's Button

Common Issues: Powdery mildew, aphids, root rot, lack of flowering
Solutions: For powdery mildew, improve air circulation and apply a fungicide. Control aphids with insecticidal soap. Prevent root rot by ensuring well-draining soil and avoiding overwatering. Provide sufficient sunlight to encourage flowering.

Flowering Kale

Common Issues: Aphids, Cabbage worms, Root rot, Bolting (premature flowering)
Solutions: Aphids: Insecticidal soap or neem oil. Cabbage worms: Handpick or use Bacillus thuringiensis (Bt). Root rot: Improve drainage and reduce watering. Bolting: Keep plants cool and well-watered.

❓ Frequently Asked Questions — Comparing These Plants

Bachelor's Button

What are the light requirements for Bachelor's Button?

Bachelor’s Buttons require at least 6-8 hours of direct sunlight each day to thrive. Insufficient light can result in leggy growth, fewer blooms, and pale foliage. Choose a location in your garden that receives full sun throughout the day. If growing indoors, place them near a south-facing window where they can receive ample sunlight.

How do I care for Bachelor's Button?

Bachelor’s Buttons thrive in full sun and well-drained soil. Water regularly, especially during dry periods, but avoid overwatering to prevent root rot. Fertilize with a balanced, slow-release fertilizer in spring to encourage abundant blooms. Deadhead spent flowers regularly to promote continuous flowering throughout the season. These plants are relatively cold-hardy but may benefit from a layer of mulch in colder climates.

How do I propagate Bachelor's Button?

Bachelor’s Buttons are primarily propagated by seed. Allow some flowers to go to seed and collect the seeds once they are dry. Sow the seeds in spring or fall in well-drained soil. Keep the soil consistently moist until germination. Thin seedlings to ensure proper spacing.

Flowering Kale

What are the light requirements for Flowering Kale?

Flowering Kale needs at least six hours of direct sunlight per day to develop its best color. Insufficient light can lead to leggy growth and dull coloration. When planting, choose a location that receives full sun exposure. If growing in containers, rotate the plants regularly to ensure even light exposure on all sides.

How do I care for Flowering Kale?

Flowering Kale thrives in cool temperatures (40-70°F) and requires at least 6 hours of sunlight daily. Plant in well-draining soil, enriched with compost or other organic matter. Water regularly, keeping the soil consistently moist but not waterlogged. Fertilize every 2-3 weeks with a balanced fertilizer during the growing season to promote vibrant color.

How do I propagate Flowering Kale?

Flowering Kale is primarily grown from seed, but propagation through stem cuttings is possible, though less common. Take stem cuttings from healthy, non-flowering shoots in late summer or early fall. Dip the cut end in rooting hormone and plant in a well-draining potting mix. Keep the cuttings moist and in a warm, humid environment until roots develop.

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