Hardy Geranium vs Kohlrabi Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Hardy Geranium
Geranium spp.
Hardy Geraniums are herbaceous perennials known for their resilience and attractive foliage. They form mounds of often deeply lobed or divided leaves, ranging in color from green to bronze, sometimes with interesting patterns. They are primarily outdoor plants, valued for their long blooming period, producing saucer-shaped flowers in shades of pink, purple, blue, white, and magenta. While some species can tolerate indoor conditions with sufficient light, they are generally grown outdoors in gardens and borders for their ease of care and ability to suppress weeds.
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.
Quick Plant Comparison
| Feature | Hardy Geranium | Kohlrabi |
|---|---|---|
| Light | Full sun to partial shade. Requires at least 6 hours of direct sunlight for optimal flowering. | Full sun (at least 6 hours of direct sunlight daily) |
| Watering | Every 7-10 days outdoors, depending on weather conditions. | Every 2-3 days outdoors, depending on weather conditions |
| Humidity | 40-60% | 40-60% |
| Temperature | 15-24°C | 15-24°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | Indoors: 30-60 cm (unlikely to thrive). Outdoors: 30-90 cm. | 30-45 cm (outdoors) |
| Pet Safety | ❌ Toxic To Pets | ✅ Safe |
| Soil | Well-draining soil. A mix of garden soil, compost, and perlite is suitable. | Well-draining, fertile soil rich in organic matter |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 15 minutes weekly (deadheading, watering). | 15-30 minutes weekly |
🔬 Botanical Information — Comparing These Plants
Hardy Geranium
| Scientific Name | Geranium spp. |
|---|---|
| Family | Geraniaceae |
| Native To | Various species originate from different regions worldwide, including Europe, Asia, and North America. |
| Also Known As | Hardy Geranium, Cranesbill |
| Leaves | Leaves are typically palmate or deeply lobed, ranging in color from green to bronze, sometimes with interesting patterns or markings. Leaf texture can vary from smooth to slightly hairy. |
| Flowers | Flowers are saucer-shaped, with five petals, and come in a variety of colors, including pink, purple, blue, white, and magenta. Flowering is profuse and long-lasting outdoors. Indoors, flowering is rare and significantly reduced. |
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. |
📏 Size & Growth — Plant Comparison
Hardy Geranium
Kohlrabi
🌱 Propagation — Comparing Plant Growth
Hardy Geranium
Methods: Division, Stem cuttings, Seed
Difficulty: Easy
Tips: Divide established clumps in spring or fall. Take stem cuttings in late spring or early summer and root in well-draining soil. Seeds can be sown in spring after a period of cold stratification.
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.
✨ Benefits & Features — Comparing Plant Value
Hardy Geranium
Hardy Geraniums are known for their long blooming period, often flowering from late spring to fall. Their foliage can also be quite attractive, with some varieties displaying interesting colors and patterns.
- ✓ Attracts pollinators to the garden.
- ✓ Provides long-lasting color in the landscape.
- ✓ Deer resistant, reducing garden damage.
- ✓ Suppresses weeds, reducing maintenance.
- ✓ Relatively low-maintenance once established.
- ⚠️ Toxic to pets
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
📅 Maintenance Schedule — Plant Care Comparison
Hardy Geranium
Kohlrabi
🌞 Light Requirements
Hardy Geranium
Full sun to partial shade. Requires at least 6 hours of direct sunlight for optimal flowering.
Low light tolerant: ❌ No
Kohlrabi
Full sun (at least 6 hours of direct sunlight daily)
Low light tolerant: ❌ No
💧 Watering Needs
Hardy Geranium
Water thoroughly when the top inch of soil feels dry. Avoid overwatering, as this can lead to root rot. Ensure good drainage.
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.
🌡️ Temperature & Humidity
Hardy Geranium
Temperature: 15-24°C
Humidity: 40-60%
Kohlrabi
Temperature: 15-24°C
Humidity: 40-60%
🤔 Which Plant Is Right For You?
Hardy Geranium
Geranium spp.Gardeners looking for low-maintenance, long-blooming perennials for their outdoor beds and borders.
✅ Choose This Plant If...
- You want a low-maintenance perennial for your garden.
- You need a plant that is deer resistant.
- You want to attract pollinators to your garden.
- You desire a long blooming period.
- You need a plant that can suppress weeds.
❌ Skip This Plant If...
- You have pets that might ingest the plant.
- You cannot provide adequate sunlight for outdoor plants indoors.
- You are looking for a plant that thrives indoors with minimal care.
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.
🎯 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
Hardy Geranium Care Tips
Hardy Geraniums are primarily outdoor plants. While they can be attempted indoors, providing adequate light and preventing pests can be challenging. They require well-draining soil, regular watering, and occasional fertilization. Indoor flowering is unlikely.
- Deadhead spent flowers regularly to encourage more blooms.
- Provide well-draining soil to prevent root rot.
- Fertilize in spring with a balanced slow-release fertilizer.
- Divide established clumps every few years to maintain vigor.
- Water deeply but infrequently, allowing the soil to dry out slightly between waterings.
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.
⚠️ Common Problems & Solutions — Plant Care Comparison
Hardy Geranium
Kohlrabi
❓ Frequently Asked Questions — Comparing These Plants
Hardy Geranium
What are the light requirements for Hardy Geranium?
Hardy Geraniums thrive best in locations that receive at least six hours of sunlight per day, although they can tolerate partial shade. In hotter climates, providing some afternoon shade can help prevent leaf scorch. When planting, consider the amount of sunlight your garden receives at different times of the day and choose a location that provides the optimal balance of light and shade.
How do I care for Hardy Geranium?
Hardy Geraniums are remarkably easy to care for, making them ideal for gardeners of all levels. Plant them in well-draining soil in a location that receives full sun to partial shade. Water regularly, especially during dry periods, but avoid overwatering, which can lead to root rot. Fertilize in spring with a balanced fertilizer to promote healthy growth and abundant blooms.
How do I propagate Hardy Geranium?
Hardy Geraniums can be easily propagated through division, stem cuttings, or seed. For division, carefully dig up the plant in early spring or fall and divide the root ball into smaller sections, each with healthy roots and foliage. Replant the divisions in well-draining soil.
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.
Last updated: April 22, 2026 — Plant care data reviewed and verified by our editorial team.