Flowering Onion vs Natal Plum 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.
Natal Plum
Carissa macrocarpa
Carissa macrocarpa, or Natal Plum, is a dense, evergreen shrub or small tree known for its glossy, dark green leaves and fragrant, star-shaped white flowers. It produces edible, plum-like red fruits that are rich in vitamin C. While it can be grown in containers, it's primarily an outdoor plant, thriving in warm climates. People grow it for its ornamental value, edible fruit, and use as a security hedge due to its thorny branches. It's not ideally suited as an indoor plant due to high light requirements and potential size.
Quick Plant Comparison
| Feature | Flowering Onion | Natal Plum |
|---|---|---|
| Light | Full sun (at least 6-8 hours of direct sunlight per day) | Full sun to partial shade. Requires at least 6 hours of direct sunlight daily to thrive and produce fruit. |
| Watering | Every 1-2 weeks during the growing season, less frequently during dormancy. | Every 7-14 days, depending on environmental conditions and pot size. |
| Humidity | 40-60% | 40-60% |
| Temperature | 15-25°C | 18-27°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | Variable, depending on the species, but typically 30-150 cm outdoors. Indoors, expect smaller sizes if grown in containers. | Indoors: Rarely exceeds 1-2 meters. Outdoors: Up to 4 meters. |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining soil, such as a mix of potting soil, sand, and perlite. | Well-draining soil mix, such as a combination of potting soil, perlite, and sand. |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 10 minutes weekly during the growing season. | 30 minutes weekly (including watering, pruning, and pest control) |
🔬 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. |
Natal Plum
| Scientific Name | Carissa macrocarpa |
|---|---|
| Family | Apocynaceae |
| Native To | South Africa |
| Also Known As | Natal Plum, Large Num-Num |
| Leaves | The leaves are glossy, dark green, and oval-shaped, measuring 2-5 cm in length. They are arranged oppositely on the stems and have a leathery texture. |
| Flowers | Natal Plum produces fragrant, star-shaped white flowers in spring and summer. While it can flower indoors with sufficient light, fruit production is less common. |
📏 Size & Growth — Plant Comparison
Flowering Onion
Natal Plum
🌱 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.
Natal Plum
Methods: Stem cuttings, Seed
Difficulty: Moderate
Tips: Take semi-hardwood cuttings in spring or summer. Dip the cut end in rooting hormone and plant in a well-draining potting mix. Keep the soil moist and provide warmth and humidity.
✨ 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
Natal Plum
The Natal Plum is unique for its combination of fragrant flowers, edible fruit, and thorny branches. Its drought tolerance makes it a suitable choice for xeriscaping.
- ✓ Provides edible fruit rich in Vitamin C
- ✓ Offers fragrant flowers that attract pollinators
- ✓ Acts as a natural security barrier due to its thorns
- ✓ Adds an ornamental touch to gardens with its glossy foliage
- ✓ Can be used in traditional medicine (with caution and expert knowledge)
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Flowering Onion
Natal Plum
🌞 Light Requirements
Flowering Onion
Full sun (at least 6-8 hours of direct sunlight per day)
Low light tolerant: ❌ No
Natal Plum
Full sun to partial shade. Requires at least 6 hours of direct sunlight daily to thrive and produce fruit.
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.
Natal Plum
Water deeply when the top inch of soil is dry. Avoid overwatering, which can lead to root rot. Allow the soil to dry slightly between waterings. Signs of underwatering include wilting leaves; overwatering includes yellowing leaves and soggy soil.
🌡️ Temperature & Humidity
Flowering Onion
Temperature: 15-25°C
Humidity: 40-60%
Natal Plum
Temperature: 18-27°C
Humidity: 40-60%
🤔 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
Natal Plum
Carissa macrocarpaExperienced gardeners in warm climates who want an ornamental shrub with edible fruit, and who can ensure it is kept away from pets.
✅ Choose This Plant If...
- You live in a warm climate with plenty of sunshine.
- You want an ornamental shrub with fragrant flowers and edible fruit.
- You need a natural barrier or security hedge.
- You are an experienced gardener looking for a new challenge.
- You are willing to provide the specific care this plant needs.
❌ Skip This Plant If...
- You have pets or small children due to the plant's toxicity.
- You live in a cold climate with limited sunlight.
- You are a beginner gardener.
- You don't have space for a large shrub.
- 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
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
Natal Plum Care Tips
Natal Plum is primarily an outdoor plant and requires significant sunlight to thrive. Growing it indoors is challenging due to its high light needs and potential size. It needs well-draining soil, moderate watering, and occasional fertilization. Toxicity to pets is a major concern.
- Provide at least 6 hours of direct sunlight daily for optimal growth and fruit production.
- Water deeply but infrequently, allowing the soil to dry slightly between waterings.
- Fertilize regularly during the growing season with a balanced fertilizer.
- Prune regularly to maintain shape and encourage new growth.
- Protect from frost in colder climates.
⚠️ Common Problems & Solutions — Plant Care Comparison
Flowering Onion
Natal Plum
❓ 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.
Natal Plum
What are the light requirements for Natal Plum?
Natal Plum requires ample sunlight to flourish and produce its characteristic blooms and fruits. Ideally, it should receive at least 6 hours of direct sunlight per day. In regions with intense sunlight, particularly during the hottest part of the day, providing some afternoon shade can prevent leaf scorch.
How do I care for Natal Plum?
Natal Plum thrives in full sun to partial shade. Ensure at least 6 hours of sunlight daily for optimal flowering and fruit production. Water thoroughly when the top inch of soil feels dry, allowing excess water to drain. Avoid overwatering, which can lead to root rot. Maintain moderate humidity, especially indoors.
How do I propagate Natal Plum?
Natal Plum can be propagated through stem cuttings. Take 4-6 inch stem cuttings from healthy, non-flowering shoots in spring or summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cuttings in a well-draining potting mix. Keep the soil moist and provide bright, indirect light. Rooting typically occurs within 4-8 weeks.
Last updated: April 27, 2026 — Plant care data reviewed and verified by our editorial team.