Flowering Onion vs Lysimachia Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
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.
Lysimachia
Lysimachia nummularia
Lysimachia nummularia, commonly known as Creeping Jenny or Moneywort, is a perennial ground cover characterized by its trailing stems and rounded, coin-like leaves. It typically grows to only a few inches in height but can spread extensively. While primarily an outdoor plant, it is sometimes grown in hanging baskets or containers indoors. People grow it for its attractive foliage and ability to quickly cover ground, creating a lush, green carpet. Its vibrant green or golden foliage adds visual interest to gardens and landscapes. It is not ideally suited for long-term indoor growth.
Quick Plant Comparison
| Feature | Flowering Onion | Lysimachia |
|---|---|---|
| Light | Full sun (at least 6-8 hours of direct sunlight per day) | Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours daily. |
| Watering | Every 1-2 weeks during the growing season, less frequently during dormancy. | Every 3-7 days, depending on light and temperature. |
| Humidity | 40-60% | 30-50% |
| Temperature | 15-25°C | 15-24°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. | 2-10 cm (indoors) |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining soil, such as a mix of potting soil, sand, and perlite. | Well-draining potting mix or garden soil. |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 10 minutes weekly during the growing season. | 15 minutes weekly |
🔬 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. |
Lysimachia
| Scientific Name | Lysimachia nummularia |
|---|---|
| Family | Primulaceae |
| Native To | Europe |
| Also Known As | Creeping Jenny, Moneywort, Twopenny Grass |
| Leaves | Rounded, coin-like leaves that are typically bright green, but some varieties have golden or chartreuse foliage. Leaves are small, usually less than an inch in diameter, and have a smooth texture. |
| Flowers | It may produce small, yellow, cup-shaped flowers in the summer, but flowering is rare indoors. |
📏 Size & Growth — Plant Comparison
Flowering Onion
Lysimachia
🌱 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.
Lysimachia
Methods: Stem cuttings, Division
Difficulty: Easy
Tips: Take stem cuttings and place them in water or directly into moist soil. Keep the soil consistently moist until roots develop. Division can be done by separating rooted sections of the plant.
✨ 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
Lysimachia
Its trailing growth habit and coin-shaped leaves make it a unique and attractive ground cover. It can tolerate a range of soil conditions and is relatively easy to propagate.
- ✓ Provides ground cover and helps prevent soil erosion.
- ✓ Adds visual interest with its bright green or golden foliage.
- ✓ Can be used in hanging baskets or containers.
- ✓ Relatively easy to propagate.
- ✓ Can tolerate a range of soil conditions.
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Flowering Onion
Lysimachia
🌞 Light Requirements
Flowering Onion
Full sun (at least 6-8 hours of direct sunlight per day)
Low light tolerant: ❌ No
Lysimachia
Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours 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.
Lysimachia
Water thoroughly when the top inch of soil feels dry. Avoid overwatering, as it can lead to root rot. Signs of underwatering include wilting leaves. Signs of overwatering include yellowing leaves and soggy soil.
🌡️ Temperature & Humidity
Flowering Onion
Temperature: 15-25°C
Humidity: 40-60%
Lysimachia
Temperature: 15-24°C
Humidity: 30-50%
🤔 Which Plant Is Right For You?
Flowering Onion
Allium spp.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
Lysimachia
Lysimachia nummulariaExperienced gardeners looking for a ground cover for outdoor spaces or those willing to provide very bright light and manage its growth indoors.
✅ Choose This Plant If...
- You want a fast-growing ground cover for your garden.
- You have a very bright, sunny indoor space.
- You enjoy the look of trailing foliage in hanging baskets.
- You want a plant that is relatively easy to propagate.
- You are experienced with managing potentially aggressive plants.
❌ Skip This Plant If...
- You have pets that may ingest the plant.
- You have limited sunlight indoors.
- You are looking for a low-maintenance indoor plant.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Flowering Onion has moderate growth, while Lysimachia 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
Lysimachia Care Tips
Creeping Jenny is relatively easy to care for outdoors, but it can be challenging indoors due to its high light requirements and potential for aggressive growth. It needs very bright light and well-draining soil. Overwatering is a common problem. Regular pruning is needed to control its spread.
- Provide bright, indirect light with some direct sun exposure.
- Water thoroughly when the top inch of soil feels dry, but avoid overwatering.
- Fertilize regularly during the growing season.
- Prune regularly to control its spread and maintain its shape.
- Monitor for pests and treat promptly.
⚠️ Common Problems & Solutions — Plant Care Comparison
Flowering Onion
Lysimachia
❓ 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.
Lysimachia
What are the light requirements for Lysimachia?
Lysimachia prefers partial to full sunlight, though the specific light needs vary depending on the species. Generally, plants need at least 4-6 hours of direct sunlight per day to thrive and produce abundant blooms. In hotter climates, providing some afternoon shade can prevent leaf scorch. Insufficient light can result in leggy growth, reduced flowering, and pale foliage.
How do I care for Lysimachia?
Lysimachia thrives in moist, well-draining soil. Water regularly, especially during dry periods, but avoid overwatering to prevent root rot. Plant in a location that receives partial to full sunlight, depending on the specific species. Fertilize monthly during the growing season (spring and summer) with a balanced liquid fertilizer to encourage blooming. Prune regularly to maintain shape and remove any dead or damaged foliage.
How do I propagate Lysimachia?
Lysimachia can be propagated easily through division, stem cuttings, and, in some species, keikis.
Last updated: April 24, 2026 — Plant care data reviewed and verified by our editorial team.