Empress Tree vs Kale Plant Comparison

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

Empress Tree

Empress Tree

Paulownia tomentosa

VS
Kale

Kale

Brassica oleracea var. sabellica

Empress Tree

Empress Tree

Paulownia tomentosa

The Empress Tree is a fast-growing deciduous tree known for its large, heart-shaped leaves and fragrant, showy purple flowers that bloom in early spring before the leaves emerge. It is primarily an outdoor tree, reaching heights of 30-60 feet. People grow it for its ornamental value, providing shade and adding a striking visual element to landscapes. While it can be grown in containers, its rapid growth and large size make it challenging to maintain indoors long-term. It is considered invasive in some regions due to its prolific seed production and ability to colonize disturbed areas.

Paulowniaceae Central and Western China
✨ Features: Fast growth, large leaves, fragrant flowers
📖 Read Complete Empress Tree Guide
Kale

Kale

Brassica oleracea var. sabellica

Kale is a leafy green vegetable belonging to the cabbage family. It's characterized by its curly or frilly leaves, which can range in color from dark green to purple. Kale is primarily grown outdoors as a cool-season crop, thriving in gardens and farms. People grow kale for its nutritional value, as it's packed with vitamins and minerals. It's a versatile vegetable used in salads, smoothies, soups, and as a cooked side dish. While technically possible to grow indoors, it requires very bright light and cool temperatures to thrive, making it challenging for most home environments.

Brassicaceae Eastern Mediterranean and Asia Minor
✨ Features: High nutritional value, cold-hardy
📖 Read Complete Kale Guide

Quick Plant Comparison

Feature Empress Tree Kale
Light Full sun (at least 6 hours of direct sunlight daily) Full sun (at least 6-8 hours of direct sunlight daily)
Watering Every 1-2 weeks, depending on weather and soil drainage Every 2-5 days, depending on weather and soil drainage
Humidity 30-50% 40-60%
Temperature 15-27°C 10-24°C
Care Level Expert Expert
Growth Rate Fast Moderate
Max Height Difficult to maintain indoors. Outdoors: 9-18 meters (30-60 feet) 30-60 cm (outdoors)
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining soil, such as a mix of loam, sand, and compost Well-draining, fertile soil rich in organic matter
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 30 minutes weekly (watering, pruning, monitoring for pests) 30 minutes weekly (weeding, watering, pest control)

🔬 Botanical Information — Comparing These Plants

Empress Tree

Scientific Name Paulownia tomentosa
Family Paulowniaceae
Native To Central and Western China
Also Known As Empress Tree, Princess Tree, Foxglove Tree
Leaves The leaves are very large, heart-shaped (cordate), and typically 15-40 cm (6-16 inches) wide. They are a medium green color and have a slightly fuzzy texture when young.
Flowers The Empress Tree produces large, showy panicles of fragrant, pale purple flowers in early spring, before the leaves emerge. Flowering is rare indoors.

Kale

Scientific Name Brassica oleracea var. sabellica
Family Brassicaceae
Native To Eastern Mediterranean and Asia Minor
Also Known As Kale, Borecole
Leaves Kale leaves vary in shape and texture depending on the variety. They can be curly, frilly, or flat, and range in color from dark green to purple. The leaves are typically large, ranging from 15-30 cm in length, and have a slightly waxy texture.
Flowers Kale will flower if allowed to bolt (go to seed), producing small, yellow flowers similar to other members of the Brassica family. Flowering is more common in the second year of growth or when exposed to prolonged periods of heat. It rarely flowers indoors.

📏 Size & Growth — Plant Comparison

Empress Tree

Height Difficult to maintain indoors. Outdoors: 9-18 meters (30-60 feet)
Spread Outdoors: 6-12 meters (20-40 feet)
Growth Rate Fast
Growth Pattern Upright, spreading tree with a rounded crown. It grows rapidly, adding several feet of height each year, especially when young.

Kale

Height 30-60 cm (outdoors)
Spread 30-60 cm
Growth Rate Moderate
Growth Pattern Kale grows upright with a rosette of leaves emerging from a central stem. The leaves can be curly, frilly, or flat, depending on the variety. It typically grows to a height of 30-60 cm.

🌱 Propagation — Comparing Plant Growth

Empress Tree

Methods: Seeds, root cuttings

Difficulty: Moderate

Tips: For seeds, stratify them in the refrigerator for a few weeks before sowing. Root cuttings should be taken in late winter or early spring.

Kale

Methods: Seed

Difficulty: Easy

Tips: Start seeds indoors 6-8 weeks before the last frost or direct sow outdoors after the last frost. Ensure proper soil moisture and temperature for germination.

✨ Benefits & Features — Comparing Plant Value

Empress Tree

The Empress Tree is distinguished by its exceptionally large leaves and early spring blooms, which appear before the leaves emerge. Its rapid growth rate also sets it apart from many other ornamental trees.

  • ✓ Provides shade in the summer
  • ✓ Offers beautiful spring blooms
  • ✓ Attracts pollinators to the garden
  • ✓ Adds a unique architectural element to the landscape
  • ✓ Fast growth provides quick results.
  • ⚠️ Toxic to pets

Kale

Kale is known for its ruffled leaves and cold hardiness, allowing it to be grown in cooler climates. It's also a highly nutritious vegetable, making it a popular choice for health-conscious individuals. Its ability to withstand frost allows for late-season harvests.

  • ✓ High in vitamins A, C, and K
  • ✓ Good source of fiber
  • ✓ Rich in antioxidants
  • ✓ Supports healthy digestion
  • ✓ Adds visual appeal to a vegetable garden
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Empress Tree

Repotting Not recommended for indoor growing due to rapid growth. Outdoor trees do not need repotting.
Pruning Prune in late winter or early spring to remove dead or damaged branches and to shape the tree.
Fertilizing Balanced fertilizer (10-10-10) in early spring, following package instructions. Avoid over-fertilizing.
Seasonal Care In spring, fertilize and prune. In summer, water regularly. In fall, collect seeds if desired. In winter, protect young trees from frost.

Kale

Repotting Not applicable, as it's typically grown directly in the ground outdoors. If grown in a container, repotting may be needed if the plant becomes root-bound.
Pruning Remove yellowing or damaged leaves to encourage new growth.
Fertilizing Balanced fertilizer (10-10-10) every 4-6 weeks during the growing season, diluted to half strength
Seasonal Care Spring/Summer: Consistent watering and fertilization. Fall/Winter: Harvest before heavy frost, protect from extreme cold.

🌞 Light Requirements

Empress Tree

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

Low light tolerant: ❌ No

Kale

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

Low light tolerant: ❌ No

💧 Watering Needs

Empress Tree

Water deeply when the top few inches of soil are dry, especially during the growing season. Avoid overwatering, which can lead to root rot. In containers, ensure proper drainage. Reduce watering in the winter when the tree is dormant. Signs of underwatering include wilting leaves; overwatering includes yellowing leaves and soggy soil.

Kale

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. Check soil moisture regularly, especially during hot weather. Signs of underwatering include wilting leaves, while overwatering can cause yellowing and mushy leaves.

🌡️ Temperature & Humidity

Empress Tree

Temperature: 15-27°C

Humidity: 30-50%

Kale

Temperature: 10-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Empress Tree

Empress Tree

Paulownia tomentosa
Care: Expert Time: 30 minutes weekly (watering, pruning, monitoring for pests) Beginner: No

Gardeners with large outdoor spaces who appreciate fast-growing shade trees with showy flowers.

✅ Choose This Plant If...

  • You want a fast-growing shade tree
  • You appreciate fragrant, showy purple flowers in early spring
  • You have a large outdoor space to accommodate its size
  • You want a tree that attracts pollinators
  • You are willing to manage its potential for invasive spread.

❌ Skip This Plant If...

  • You have a small garden or limited space
  • You are looking for an easy-to-care-for indoor plant
  • You live in an area where it is considered invasive
📍 Ideal Location: Outdoor garden or landscape with full sun and well-draining soil
🎨 Style: Traditional, Naturalistic
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Paulownia tomentosa is toxic to horses. The toxic principle is unknown. Symptoms include gastrointestinal upset.
Kale

Kale

Brassica oleracea var. sabellica
Care: Expert Time: 30 minutes weekly (weeding, watering, pest control) Beginner: No

Gardeners with outdoor space and a desire for a nutritious leafy green vegetable.

✅ Choose This Plant If...

  • You have a sunny outdoor garden space.
  • You want a highly nutritious leafy green vegetable.
  • You live in a region with cool growing seasons.
  • You enjoy cooking with versatile vegetables.
  • You are experienced with managing garden pests and diseases.

❌ Skip This Plant If...

  • You lack a sunny outdoor space.
  • You are looking for an easy-to-grow indoor plant.
  • You have pets that are prone to eating plants.
  • You live in a very hot climate where kale struggles to grow.
  • You dislike the taste of kale.
📍 Ideal Location: Outdoor garden or raised bed with full sun exposure
🎨 Style: Rustic, Cottage garden, Farmhouse
🏠 Apartment Friendly: No
⚠️ Kale contains isothiocyanates, which can cause gastrointestinal irritation in dogs, cats, and horses if consumed in large quantities. Symptoms include vomiting, diarrhea, and abdominal discomfort. According to the ASPCA, plants in the Brassica genus are 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

☀️

Empress Tree needs full sun (at least 6 hours of direct sunlight daily), while Kale prefers full sun (at least 6-8 hours of direct sunlight daily).

📈

Empress Tree has fast growth, while Kale grows moderate.

💡 Pro Tips For Comparing These Plants

Empress Tree Care Tips

The Empress Tree is primarily an outdoor tree that requires full sun and well-draining soil. Growing it indoors is extremely challenging due to its size and light requirements. It is best suited for outdoor landscapes where it has ample space to grow. Requires regular pruning to maintain shape and control size.

  • Plant in well-draining soil to prevent root rot.
  • Water deeply but infrequently, allowing the soil to dry out between waterings.
  • Prune regularly to maintain shape and control size.
  • Fertilize in early spring with a balanced fertilizer.
  • Monitor for pests and diseases and treat promptly.
❄️ Winter: Protect young trees from frost damage by wrapping the trunk with burlap. Reduce watering during dormancy.
☀️ Summer: Water regularly during hot, dry periods. Monitor for pests and diseases. Provide shade during extreme heat if possible.

Kale Care Tips

Kale is primarily an outdoor plant that requires full sun and cool temperatures to thrive. Growing it indoors is challenging due to the need for intense light and specific temperature conditions. It's susceptible to pests and diseases, requiring vigilant monitoring and treatment. Indoor growth is often stunted and less productive compared to outdoor cultivation.

  • Provide consistent watering, especially during dry periods.
  • Fertilize regularly with a balanced fertilizer.
  • Monitor for pests and diseases and treat promptly.
  • Harvest leaves regularly to encourage continued growth.
  • Protect from extreme cold or heat.
❄️ Winter: Protect kale from extreme cold with row covers or mulch. Reduce watering during dormancy. Harvest leaves as needed throughout the winter.
☀️ Summer: Provide shade during the hottest part of the day to prevent bolting. Ensure consistent watering to prevent stress. Monitor for pests and diseases, which are more prevalent in warm weather.

⚠️ Common Problems & Solutions — Plant Care Comparison

Empress Tree

Common Issues: Root rot, leaf spot, powdery mildew, invasive spread
Solutions: Ensure well-draining soil and avoid overwatering to prevent root rot. Use a fungicide for leaf spot and powdery mildew. Control invasive spread by removing seedlings and preventing seed production.

Kale

Common Issues: Aphids, cabbage worms, clubroot, bolting
Solutions: Aphids: Insecticidal soap or neem oil. Cabbage worms: Handpick or use Bacillus thuringiensis (Bt). Clubroot: Improve soil drainage and pH. Bolting: Provide shade and consistent watering.

❓ Frequently Asked Questions — Comparing These Plants

Empress Tree

What are the light requirements for Empress Tree?

Empress Trees need bright, indirect light to thrive indoors. Insufficient light will result in leggy growth and smaller leaves. An east-facing window is ideal, providing gentle morning sun. A south-facing window can also work, but shield the plant from intense midday sun with a sheer curtain. Rotate the plant regularly to ensure even light exposure on all sides. If natural light is insufficient, supplement with a grow light. Place the grow light 12-18 inches away from the plant. Observe the plant’s response to the light and adjust accordingly. A lack of light causes stunted growth and pale foliage.

How do I care for Empress Tree?

Empress Tree requires bright, indirect light; too much direct sun can scorch the leaves. Water thoroughly when the top inch of soil is dry, ensuring good drainage to prevent root rot. A well-draining potting mix is crucial. Maintain a temperature between 65-75°F (18-24°C). Humidity levels should be moderate to high; consider using a humidifier or pebble tray. Fertilize monthly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Prune regularly to maintain shape and encourage bushier growth; remove any dead or yellowing leaves. Repot annually in spring, increasing pot size as needed. Monitor for pests like spider mites and aphids, and treat promptly with insecticidal soap. Providing stable conditions are key to health and growth.

How do I propagate Empress Tree?

Empress Tree can be propagated through stem cuttings or air layering. For stem cuttings, take a 4-6 inch cutting from a healthy stem in spring. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cutting in a well-draining potting mix and keep it moist. Cover with a plastic bag to increase humidity. Roots should develop in 4-6 weeks. For air layering, make a shallow cut on a stem and wrap it with moist sphagnum moss. Cover the moss with plastic wrap and secure it with tape. Keep the moss moist. Roots should develop in several weeks. Once roots are visible, cut the stem below the roots and plant it in a pot. Ensure stable conditions during propagation.

Kale

What are the light requirements for Kale?

Flowering Kale requires ample sunlight to develop its vibrant colors. Aim for at least 6 hours of direct sunlight per day, especially during the fall and winter months when sunlight is less intense. Insufficient light will result in faded colors and leggy growth.

How do I care for Kale?

Flowering Kale thrives with consistent care. Plant in well-draining soil, preferably a slightly acidic to neutral pH (6.0-7.0). Provide at least 6 hours of sunlight daily, more is better, especially in fall and winter. Water regularly, keeping the soil consistently moist but not waterlogged. Fertilize every 2-3 weeks with a balanced liquid fertilizer, especially during active growth and bloom.

How do I propagate Kale?

Flowering Kale is primarily grown from seed, but propagation through stem cuttings is possible, though less common. Division is not typically practiced with Flowering Kale.

Last updated: May 9, 2026 — Plant care data reviewed and verified by our editorial team.