Kohlrabi vs Leatherleaf Fern Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Kohlrabi
Brassica oleracea var. gongylodes
Kohlrabi is a biennial vegetable cultivated as an annual, known for its swollen, globular stem that grows above ground. It features a crisp, mild flavor similar to a turnip or cabbage. The plant has long-stalked leaves emerging from the bulbous stem. It is primarily grown outdoors in gardens and farms for its edible stem and leaves. While it can be started indoors, it requires full sun and ample space to thrive, making it challenging to grow to maturity indoors. People grow kohlrabi for its unique texture and flavor in salads, stir-fries, and other culinary applications.
Leatherleaf Fern
Rumohra adiantiformis
Leatherleaf fern is a perennial fern characterized by its leathery, triangular fronds that are deeply divided into smaller leaflets (pinnules). It's primarily an outdoor plant in warmer climates, often found in forests and rocky areas. It is widely cultivated commercially for use in floral arrangements due to its long-lasting foliage. While it can be grown indoors, it requires specific conditions to thrive and often struggles to adapt to typical indoor environments. Its popularity stems from its attractive foliage and durability as a cut flower.
Quick Plant Comparison
| Feature | Kohlrabi | Leatherleaf Fern |
|---|---|---|
| Light | Full sun (at least 6 hours of direct sunlight daily) | Bright, indirect light. Avoid direct sunlight, which can scorch the fronds. |
| Watering | Every 2-3 days outdoors, depending on weather conditions | Every 7-10 days, depending on environmental conditions |
| Humidity | 40-60% | 60-80% |
| Temperature | 15-24°C | 18-24°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | 30-45 cm (outdoors) | 30-60 cm indoors (can be larger outdoors) |
| Pet Safety | ✅ Safe | ✅ Safe |
| Soil | Well-draining, fertile soil rich in organic matter | Well-draining, slightly acidic potting mix rich in organic matter. A mix of peat moss, perlite, and potting soil works well. |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 15-30 minutes weekly | 15 minutes weekly |
🔬 Botanical Information — Comparing These Plants
Kohlrabi
| Scientific Name | Brassica oleracea var. gongylodes |
|---|---|
| Family | Brassicaceae |
| Native To | Northern Europe |
| Also Known As | German turnip, turnip cabbage |
| Leaves | The leaves of kohlrabi are typically bluish-green, broad, and have a slightly waxy texture. They are attached to the stem by long, slender stalks. The leaf shape can vary, but they are generally oval or rounded with slightly serrated edges. |
| Flowers | Kohlrabi will flower in its second year if allowed to overwinter. The flowers are typical of the Brassica family, with four petals arranged in a cross shape, usually yellow or white. Flowering is rare when grown as an annual for its bulb. |
Leatherleaf Fern
| Scientific Name | Rumohra adiantiformis |
|---|---|
| Family | Dryopteridaceae |
| Native To | Southern Hemisphere: South Africa, Australia, New Zealand, South America |
| Also Known As | Leatherleaf Fern, Leather Fern, Iron Fern |
| Leaves | The leaves (fronds) are triangular in shape and deeply divided into numerous small, leathery leaflets (pinnules). The pinnules are a rich green color and have a slightly glossy texture. The fronds can grow up to 60 cm long and are arranged alternately along the stem. |
| Flowers | Leatherleaf ferns do not flower in the traditional sense. They reproduce via spores, which are located on the underside of the fronds. Flowering is not a consideration for indoor cultivation. |
📏 Size & Growth — Plant Comparison
Kohlrabi
Leatherleaf Fern
🌱 Propagation — Comparing Plant Growth
Kohlrabi
Methods: Seed
Difficulty: Easy
Tips: Start seeds indoors 4-6 weeks before the last frost or direct sow outdoors after the last frost. Keep soil consistently moist.
Leatherleaf Fern
Methods: Spores, Rhizome division
Difficulty: Moderate
Tips: Rhizome division is the easier method. Divide the rhizome in spring, ensuring each section has several fronds and roots. Plant in a well-draining potting mix and keep consistently moist.
✨ Benefits & Features — Comparing Plant Value
Kohlrabi
Kohlrabi is unique due to its edible, swollen stem that grows above ground, unlike root vegetables. Its mild flavor and crisp texture make it a versatile ingredient in various dishes. The plant also offers edible leaves, adding to its appeal.
- ✓ Provides fresh, nutritious vegetables
- ✓ Adds visual interest to the garden
- ✓ Encourages healthy eating habits
- ✓ Offers a unique culinary ingredient
- ✓ Supports sustainable living
- 🐾 Pet Safe
Leatherleaf Fern
The leatherleaf fern is known for its durable, leathery fronds that are commonly used in floral arrangements. Its ability to withstand handling and maintain its appearance makes it a popular choice in the floral industry. It's also relatively drought-tolerant once established outdoors, which is unusual for a fern.
- ✓ Adds a lush, green aesthetic to indoor spaces.
- ✓ Provides a calming and natural element to decor.
- ✓ Non-toxic to pets, making it a safe choice for animal lovers.
- ✓ Can be used in floral arrangements.
- ✓ Offers a unique texture and visual interest.
- 🐾 Pet Safe
📅 Maintenance Schedule — Plant Care Comparison
Kohlrabi
Leatherleaf Fern
🌞 Light Requirements
Kohlrabi
Full sun (at least 6 hours of direct sunlight daily)
Low light tolerant: ❌ No
Leatherleaf Fern
Bright, indirect light. Avoid direct sunlight, which can scorch the fronds.
Low light tolerant: ❌ No
💧 Watering Needs
Kohlrabi
Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to rot. Consistent moisture is important for bulb development. Signs of underwatering include wilting leaves and stunted growth. Overwatering can cause yellowing leaves and a mushy stem.
Leatherleaf Fern
Water thoroughly when the top inch of soil feels dry. Ensure good drainage to prevent root rot. Overwatering can lead to yellowing fronds and root rot, while underwatering causes the fronds to become dry and brittle.
🌡️ Temperature & Humidity
Kohlrabi
Temperature: 15-24°C
Humidity: 40-60%
Leatherleaf Fern
Temperature: 18-24°C
Humidity: 60-80%
🤔 Which Plant Is Right For You?
Kohlrabi
Brassica oleracea var. gongylodesGardeners looking for a unique and nutritious vegetable to grow outdoors.
✅ Choose This Plant If...
- You have a sunny garden space.
- You enjoy growing your own vegetables.
- You want a unique and nutritious addition to your diet.
- You are looking for a relatively fast-growing crop.
- You enjoy the taste of cabbage and turnips.
❌ Skip This Plant If...
- You lack sufficient outdoor space.
- You cannot provide at least 6 hours of direct sunlight daily.
- You are looking for a low-maintenance indoor plant.
Leatherleaf Fern
Rumohra adiantiformisExperienced plant enthusiasts who can provide the specific environmental conditions required for this fern to thrive indoors.
✅ Choose This Plant If...
- You appreciate the unique texture and appearance of fern foliage.
- You are looking for a long-lasting green for floral arrangements.
- You have a greenhouse or terrarium where you can provide high humidity.
- You enjoy a challenge and are willing to provide specific care.
- You want a plant that is non-toxic to pets.
❌ Skip This Plant If...
- You struggle to maintain high humidity levels in your home.
- You tend to overwater plants.
- You don't have a bright, indirectly lit space.
- You are a beginner plant owner.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Both plants have similar basic care requirements but differ in appearance and specific needs. Compare plants carefully to find the best fit for your space.
💡 Pro Tips For Comparing These Plants
Kohlrabi Care Tips
Kohlrabi is primarily an outdoor plant that requires full sun and consistent moisture. Growing it indoors is challenging due to the high light requirements and space needed for bulb development. It's best suited for experienced gardeners with outdoor space.
- Start seeds indoors for an earlier harvest.
- Ensure well-draining soil to prevent rot.
- Provide consistent moisture for optimal bulb development.
- Fertilize regularly during the growing season.
- Protect from pests like aphids and cabbage worms.
Leatherleaf Fern Care Tips
Leatherleaf fern is challenging to grow indoors due to its high humidity and specific light requirements. It needs consistent moisture, good air circulation, and protection from direct sunlight. Maintaining adequate humidity is crucial for its survival indoors. It is primarily an outdoor plant and requires expert care to thrive as a houseplant.
- Maintain high humidity by using a humidifier or placing the plant on a pebble tray.
- Water thoroughly but allow the soil to dry slightly between waterings.
- Provide bright, indirect light and avoid direct sunlight.
- Fertilize regularly during the growing season with a balanced liquid fertilizer.
- Monitor for pests and treat promptly with insecticidal soap or neem oil.
⚠️ Common Problems & Solutions — Plant Care Comparison
Kohlrabi
Leatherleaf Fern
❓ Frequently Asked Questions — Comparing These Plants
Kohlrabi
What are the light requirements for Kohlrabi?
Kohlrabi thrives in full sun, requiring at least 6 hours of direct sunlight per day to produce healthy bulbs. Insufficient light can lead to leggy growth and smaller, less flavorful bulbs. In hotter climates, providing some afternoon shade can prevent the plant from bolting (prematurely going to seed). When growing indoors, place Kohlrabi near a south-facing window or use grow lights to supplement natural light. Rotate the plants regularly to ensure even light exposure on all sides. Monitor the leaves for signs of insufficient light, such as pale color or elongated stems, and adjust the light accordingly.
How do I care for Kohlrabi?
Kohlrabi requires well-draining soil rich in organic matter. Plant seeds directly in the garden or start indoors 4-6 weeks before the last frost. Space plants 6-8 inches apart in rows 12-18 inches apart. Water regularly, keeping the soil consistently moist but not waterlogged. Fertilize every 2-3 weeks with a balanced fertilizer, paying attention to potassium levels to promote strong bulb development. Kohlrabi prefers full sun but can tolerate partial shade, especially in warmer climates. Harvest when the bulb reaches 2-3 inches in diameter for the best flavor and texture. Protect from pests like cabbage worms and aphids with appropriate organic pest control methods. Rotate crops annually to prevent soilborne diseases.
How do I propagate Kohlrabi?
Kohlrabi is typically propagated by seed, but it is possible to propagate it through vegetative methods, although less common.
Leatherleaf Fern
What are the light requirements for Leatherleaf Fern?
Leatherleaf Ferns require bright, indirect light to thrive. Direct sunlight can scorch their delicate fronds, so avoid placing them in south-facing windows without any shade. An east- or north-facing window is ideal, providing gentle, diffused light. If you don’t have access to natural light, you can supplement with fluorescent grow lights. Position the lights about 12-18 inches above the plant. If the fronds start to turn pale or yellow, it may indicate that the plant is receiving too much light. Conversely, if the growth is slow and the fronds appear dark green, it may not be getting enough light. Rotate the plant regularly to ensure even exposure to light.
How do I care for Leatherleaf Fern?
Leatherleaf Ferns thrive in bright, indirect light. Avoid direct sunlight, which can scorch their delicate fronds. Water regularly, keeping the soil consistently moist but not soggy. Allow the top inch of soil to dry out slightly between waterings. Maintain high humidity levels by misting the plant regularly or placing it on a pebble tray. The ideal temperature range is between 60-75°F (15-24°C). Fertilize monthly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Repot every 1-2 years, or when the plant becomes root-bound, using a well-draining potting mix. Prune away any dead or yellowing fronds to encourage new growth. Proper air circulation is also crucial to prevent fungal diseases.
How do I propagate Leatherleaf Fern?
Leatherleaf Ferns can be propagated through division or spores. For division, carefully separate the rhizomes of a mature plant during repotting, ensuring each division has healthy roots and fronds. Plant each division in its own pot with well-draining potting mix. To propagate from spores, collect spores from the underside of mature fronds. Sow the spores on a moist surface of peat moss in a covered container. Maintain high humidity and warmth until small plantlets develop. Transplant the plantlets into individual pots once they are large enough to handle. Propagation from spores is a slow process, but it can be a rewarding experience.
Last updated: May 3, 2026 — Plant care data reviewed and verified by our editorial team.