Ice Plant vs Onion Plant Comparison

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

Ice Plant

Ice Plant

Lampranthus spectabilis

VS
Onion

Onion

Allium cepa

Ice Plant

Ice Plant

Lampranthus spectabilis

Lampranthus spectabilis, commonly known as Trailing Ice Plant, is a succulent groundcover native to South Africa. It's characterized by its vibrant, daisy-like flowers that bloom profusely in spring and summer, creating a carpet of color. The plant features fleshy, cylindrical leaves that are bluish-green. It's primarily an outdoor plant, valued for its drought tolerance and ability to stabilize slopes. While it can be grown in containers, it requires very specific conditions to thrive indoors, making it challenging for indoor cultivation. People grow it for its showy flowers and low-maintenance nature in suitable climates.

Aizoaceae South Africa
✨ Features: Drought tolerance, vibrant flowers, erosion control
📖 Read Complete Ice Plant Guide
Onion

Onion

Allium cepa

The onion (Allium cepa) is a biennial plant, typically grown as an annual, cultivated for its edible bulb. It features hollow, bluish-green leaves and a bulb that develops at the base of the plant. Onions are primarily grown outdoors in gardens or fields. While it's possible to sprout an onion indoors, it's not typically grown to full maturity as a houseplant due to its strong odor and specific environmental needs. People grow onions for culinary purposes, adding flavor to a wide variety of dishes.

Amaryllidaceae Central Asia
✨ Features: Edible bulb, pungent flavor, source of vitamins and minerals.
📖 Read Complete Onion Guide

Quick Plant Comparison

Feature Ice Plant Onion
Light Full sun (at least 6-8 hours of direct sunlight daily) Full sun (6-8 hours of direct sunlight daily)
Watering Every 2-4 weeks, depending on weather and soil drainage Every 5-7 days, depending on weather and soil drainage
Humidity 20-40% 40-60%
Temperature 15-27°C 13-24°C
Care Level Expert Expert
Growth Rate Fast Moderate
Max Height 15-30 cm Outdoors: 30-60 cm. Indoors (sprouted): Up to 30cm
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil Well-draining succulent or cactus mix Well-draining, fertile soil rich in organic matter
Beginner Friendly ❌ No With Caution
Weekly Maintenance 5 minutes weekly (mostly for occasional pruning and pest checks) 30 minutes weekly (weeding, watering, pest control)

🔬 Botanical Information — Comparing These Plants

Ice Plant

Scientific Name Lampranthus spectabilis
Family Aizoaceae
Native To South Africa
Also Known As Trailing Ice Plant, Showy Trailing Iceplant, Pink Carpet
Leaves Fleshy, cylindrical leaves that are bluish-green in color. They are typically 2-5 cm long and have a smooth texture.
Flowers Flowers profusely outdoors in spring and summer. The flowers are daisy-like, 5-8 cm in diameter, and come in a variety of colors, including pink, purple, orange, and yellow. Rarely flowers indoors.

Onion

Scientific Name Allium cepa
Family Amaryllidaceae
Native To Central Asia
Also Known As Onion, Bulb Onion, Common Onion
Leaves The leaves are hollow, cylindrical, and bluish-green, growing directly from the bulb. They are typically 30-50 cm long and taper to a point.
Flowers Onions produce a spherical umbel of small, white or purple flowers on a tall stalk. Flowering is more common in the second year of growth. Flowering rarely occurs indoors.

📏 Size & Growth — Plant Comparison

Ice Plant

Height 15-30 cm
Spread 60-90 cm (can spread aggressively outdoors)
Growth Rate Fast
Growth Pattern Trailing and spreading groundcover. It forms a dense mat of succulent foliage and can spread rapidly in favorable conditions.

Onion

Height Outdoors: 30-60 cm. Indoors (sprouted): Up to 30cm
Spread Outdoors: 10-15 cm. Indoors (sprouted): 5-10cm
Growth Rate Moderate
Growth Pattern Onions grow upright with hollow, cylindrical leaves emerging from the bulb. The bulb develops underground, gradually increasing in size as the plant matures.

🌱 Propagation — Comparing Plant Growth

Ice Plant

Methods: Stem cuttings, Seed

Difficulty: Easy

Tips: Take stem cuttings in spring or summer, allow them to callous over for a few days, and then plant them in well-draining soil. Keep the soil lightly moist until roots develop.

Onion

Methods: Seed, Bulb division

Difficulty: Easy

Tips: Start seeds indoors 8-10 weeks before the last frost or plant sets (small bulbs) directly in the garden after the last frost. For bulb division, separate small bulbs from a larger cluster and plant them individually.

✨ Benefits & Features — Comparing Plant Value

Ice Plant

Lampranthus spectabilis is known for its vibrant, daisy-like flowers that bloom profusely in spring and summer. Its drought tolerance and ability to thrive in poor soils make it a valuable plant for xeriscaping and erosion control.

  • ✓ Drought tolerance reduces water consumption.
  • ✓ Vibrant flowers enhance garden aesthetics.
  • ✓ Erosion control helps stabilize soil.
  • ✓ Attracts pollinators like bees and butterflies.
  • ✓ Low maintenance saves time and effort.
  • 🐾 Pet Safe

Onion

The onion is a bulbous plant with a distinctive pungent odor and flavor. Its layers of fleshy scales form the edible bulb, which is used in a wide variety of culinary applications.

  • ✓ Provides fresh, flavorful onions for cooking.
  • ✓ Rich in vitamins and minerals.
  • ✓ Can deter pests in the garden.
  • ✓ Offers a rewarding gardening experience.
  • ✓ Supports sustainable food practices.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Ice Plant

Repotting Not typically repotted if grown outdoors. If in a container, repot every 2-3 years or when the plant becomes root-bound.
Pruning Prune after flowering to maintain shape and encourage bushier growth. Remove any dead or damaged stems.
Fertilizing Low-nitrogen fertilizer, diluted to half strength, once in spring
Seasonal Care In winter, reduce watering significantly. In summer, ensure adequate sunlight and ventilation to prevent fungal diseases.

Onion

Repotting Not applicable as it's typically grown in the ground. If sprouted in a container, repotting is not necessary.
Pruning Remove any yellowing or damaged leaves. Cut off flower stalks to encourage bulb development.
Fertilizing Balanced fertilizer (10-10-10) applied every 4-6 weeks during the growing season at half strength
Seasonal Care In spring and summer, provide regular watering and fertilization. In fall, harvest the bulbs when the tops begin to fall over. In winter, store harvested bulbs in a cool, dry place.

🌞 Light Requirements

Ice Plant

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

Low light tolerant: ❌ No

Onion

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

Low light tolerant: ❌ No

💧 Watering Needs

Ice Plant

Water thoroughly when the soil is dry to the touch. Overwatering can lead to root rot, so ensure good drainage. Signs of overwatering include yellowing or mushy leaves. Underwatering is indicated by shriveled or wrinkled leaves.

Onion

Water deeply when the top inch of soil is dry. Avoid overwatering, which can lead to bulb rot. Signs of overwatering include yellowing leaves and a soft, mushy bulb. Underwatering is indicated by wilting leaves and stunted growth.

🌡️ Temperature & Humidity

Ice Plant

Temperature: 15-27°C

Humidity: 20-40%

Onion

Temperature: 13-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Ice Plant

Ice Plant

Lampranthus spectabilis
Care: Expert Time: 5 minutes weekly (mostly for occasional pruning and pest checks) Beginner: No

Gardeners in warm, dry climates looking for a low-maintenance, colorful groundcover.

✅ Choose This Plant If...

  • You live in a warm, sunny, and dry climate.
  • You want a low-maintenance groundcover that requires minimal watering.
  • You desire vibrant, colorful flowers that attract pollinators.
  • You need a plant for erosion control on slopes.
  • You have a rock garden or succulent garden.

❌ Skip This Plant If...

  • You live in a cold, wet climate with limited sunlight.
  • You want an easy-to-grow indoor plant.
  • You are concerned about aggressive spreading in your garden.
📍 Ideal Location: Outdoor rock garden, sunny slope, or container garden in a warm climate.
🎨 Style: Mediterranean, Coastal, Xeriscape
🏠 Apartment Friendly: No
⚠️ According to multiple sources, including the University of California, Davis, Lampranthus species are considered non-toxic to humans and animals. However, it's always best to prevent pets from ingesting any plant material.
Onion

Onion

Allium cepa
Care: Expert Time: 30 minutes weekly (weeding, watering, pest control) Beginner: With-caution

Gardeners looking to grow their own culinary onions.

✅ Choose This Plant If...

  • You want to grow your own fresh onions for cooking.
  • You have a sunny outdoor garden space.
  • You enjoy the process of nurturing plants from seed to harvest.
  • You want to control the quality and source of your food.
  • You are looking for a companion plant to deter pests in your vegetable garden.

❌ Skip This Plant If...

  • You have pets that might ingest the plant.
  • You lack a sunny outdoor space.
  • You are sensitive to strong odors.
📍 Ideal Location: Outdoor garden or raised bed with full sun exposure.
🎨 Style: Rustic, Cottage Garden, Farmhouse
🏠 Apartment Friendly: No
⚠️ All parts of the onion plant are toxic to dogs, cats, and horses. The toxic principle is N-propyl disulfide, which can cause hemolytic anemia. Symptoms include vomiting, diarrhea, weakness, and pale gums.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Ice Plant ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

☀️

Ice Plant needs full sun (at least 6-8 hours of direct sunlight daily), while Onion prefers full sun (6-8 hours of direct sunlight daily).

📈

Ice Plant has fast growth, while Onion grows moderate.

💡 Pro Tips For Comparing These Plants

Ice Plant Care Tips

Trailing Ice Plant is primarily an outdoor plant that requires full sun and well-draining soil. Indoor cultivation is challenging due to the high light requirements. It's drought-tolerant but susceptible to root rot if overwatered. It can spread aggressively in suitable outdoor conditions. Indoor growing is not recommended.

  • Provide full sun for optimal flowering.
  • Ensure excellent drainage to prevent root rot.
  • Water sparingly, allowing the soil to dry out completely between waterings.
  • Fertilize lightly in spring with a low-nitrogen fertilizer.
  • Prune after flowering to maintain shape and encourage new growth.
❄️ Winter: Reduce watering significantly during the winter months. Protect from frost in colder climates.
☀️ Summer: Ensure adequate sunlight and ventilation to prevent fungal diseases. Water more frequently during hot, dry periods.

Onion Care Tips

Onions are primarily outdoor plants requiring full sun and well-drained soil. Growing them indoors is challenging due to their need for intense sunlight and the potential for strong odors. While sprouting an onion indoors is possible, achieving a mature bulb is difficult.

  • Plant in well-drained soil amended with compost.
  • Water deeply but infrequently, allowing the soil to dry slightly between waterings.
  • Fertilize regularly during the growing season with a balanced fertilizer.
  • Protect from pests and diseases with appropriate measures.
  • Harvest when the tops begin to fall over and the bulbs are mature.
❄️ Winter: Store harvested onion bulbs in a cool, dry, and well-ventilated place. Ensure they are dry before storing to prevent rot.
☀️ Summer: Provide consistent watering and fertilization during the active growing season. Monitor for pests and diseases and take appropriate action.

⚠️ Common Problems & Solutions — Plant Care Comparison

Ice Plant

Common Issues: Root rot, Aphids, Mealybugs, Lack of flowering
Solutions: Root rot: Improve drainage and reduce watering frequency. | Aphids: Spray with insecticidal soap. | Mealybugs: Remove with a cotton swab dipped in alcohol. | Lack of flowering: Ensure adequate sunlight and proper fertilization.

Onion

Common Issues: Bulb rot, Onion maggots, Thrips, Downy mildew
Solutions: Bulb rot: Ensure well-draining soil and avoid overwatering. Onion maggots: Use row covers or apply beneficial nematodes. Thrips: Insecticidal soap or neem oil. Downy mildew: Improve air circulation and apply a fungicide.

❓ Frequently Asked Questions — Comparing These Plants

Ice Plant

What are the light requirements for Ice Plant?

Ice Plants require ample sunlight to thrive and produce their characteristic vibrant blooms. Ideally, they should receive at least 6 hours of direct sunlight each day. A south-facing window is often the best location for indoor Ice Plants. If natural light is insufficient, supplement with a grow light. Insufficient light can lead to etiolation, where the plant becomes leggy and the leaves become pale and stretched. Rotate the plant regularly to ensure even light exposure on all sides. When acclimating an Ice Plant to brighter light conditions, do so gradually to avoid sunburn. Outdoor Ice Plants should be planted in a location that receives full sun.

How do I care for Ice Plant?

Ice Plants thrive in bright, direct sunlight for at least 6 hours daily. Plant in well-draining succulent or cactus mix to prevent root rot. Water thoroughly only when the soil is completely dry, typically every 2-4 weeks, depending on the climate and pot size. Reduce watering significantly during the winter dormancy period. Maintain temperatures between 60-80°F (15-27°C). Fertilize sparingly during the growing season (spring and summer) with a diluted balanced liquid fertilizer specifically formulated for succulents. Repot only when the plant becomes root-bound. Ensure good air circulation to prevent fungal diseases. Prune back any dead or leggy growth to encourage bushier growth and more abundant blooms. Protect from frost, as Ice Plants are not cold-hardy. Monitor for pests like mealybugs and aphids, and treat promptly if detected.

How do I propagate Ice Plant?

Ice Plants are easily propagated through leaf cuttings, stem cuttings, or offsets. For leaf cuttings, allow the cut end to callous over for a few days before placing it on top of well-draining soil. Mist lightly and keep in a bright location. For stem cuttings, allow the cut end to callous over for a few days before planting it in well-draining soil. Water sparingly until roots develop. Offsets can be carefully separated from the mother plant and planted in their own pots. Ensure the soil is well-draining and provide bright, indirect light. Water sparingly until the new plants are established. Rooting hormone can be used to increase the success rate of propagation, but it is not essential.

Onion

What are the light requirements for Onion?

Flowering onions require ample sunlight to thrive and produce abundant blooms. Aim for at least 6-8 hours of direct sunlight per day. Inadequate light can lead to leggy growth, weak stems, and reduced flowering. If growing indoors, place your onion plant near a south-facing window where it can receive maximum sunlight exposure. If natural light is insufficient, supplement with grow lights. Rotate the plant regularly to ensure even light distribution and prevent it from leaning towards the light source. Monitor the foliage for signs of sunburn, which can occur if the plant is exposed to intense afternoon sun. Adjust the placement or provide shade if necessary.

How do I care for Onion?

Flowering onions thrive with proper care. Plant bulbs in well-draining soil in a sunny location. Water thoroughly after planting and then moderately, allowing the soil to dry slightly between waterings. Fertilize sparingly with a balanced fertilizer during the growing season, and increase phosphorus before blooming. Deadhead spent flowers to encourage continued blooming. Provide support for taller varieties to prevent drooping. In colder climates, protect bulbs with a layer of mulch during winter. Monitor for pests and diseases, and address promptly. Ensure good air circulation to prevent fungal issues. Repot container-grown onions every few years to refresh the soil. Regular check-ups will keep your onion plant healthy and flourishing.

How do I propagate Onion?

Flowering onions can be propagated through several methods. Division is the most common and easiest. When the plant is dormant, carefully dig up the clump and separate the bulbs. Replant the individual bulbs in well-draining soil. Stem cuttings are not typically used for onion propagation. Keiki (small plantlets that form on the flower stalk) are rare in onions. For bulb offsets, detach them carefully from the mother bulb and plant them separately. Water regularly and provide adequate sunlight. Propagation is best done in the fall or early spring. Ensure the new plants have adequate space to develop their root systems. With proper care, the propagated onions will develop into mature, flowering plants within a year or two.

Last updated: May 3, 2026 — Plant care data reviewed and verified by our editorial team.