Cedar vs Onion Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Cedar
Cedrus spp.
Cedrus species, commonly known as true cedars, are coniferous evergreen trees characterized by their aromatic wood, needle-like leaves arranged in spirals on long shoots and in dense clusters on short shoots, and barrel-shaped cones. They are large trees, typically reaching heights of 30-40 meters (100-130 feet) or more in their native habitats. Cedars are primarily outdoor trees, valued for their majestic appearance and use in landscaping. They are not naturally indoor plants and struggle to thrive in the confined conditions of indoor environments. People grow them for ornamental purposes, timber production, and their cultural significance.
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.
Quick Plant Comparison
| Feature | Cedar | Onion |
|---|---|---|
| Light | Full sun (at least 6 hours of direct sunlight per day) | Full sun (6-8 hours of direct sunlight daily) |
| Watering | Outdoors: Once or twice a week during the growing season, less frequently during dormancy. Indoors (not recommended): Extremely difficult to maintain proper moisture levels. | Every 5-7 days, depending on weather and soil drainage |
| Humidity | 30-50% | 40-60% |
| Temperature | 10-24°C | 13-24°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | Indoors: Highly unlikely to thrive; if attempted, a few feet at most. Outdoors: 30-40 meters (100-130 feet) or more. | Outdoors: 30-60 cm. Indoors (sprouted): Up to 30cm |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining, slightly acidic soil | Well-draining, fertile soil rich in organic matter |
| Beginner Friendly | ❌ No | With Caution |
| Weekly Maintenance | 1-2 hours per month (primarily for pruning and monitoring for pests/diseases) | 30 minutes weekly (weeding, watering, pest control) |
🔬 Botanical Information — Comparing These Plants
Cedar
| Scientific Name | Cedrus spp. |
|---|---|
| Family | Pinaceae |
| Native To | Mediterranean region and the Western Himalayas |
| Also Known As | Cedar, True Cedar |
| Leaves | The leaves of cedar trees are needle-like, typically 1-2 inches long, and arranged in spirals on long shoots and in dense clusters on short shoots. The color varies depending on the species, ranging from dark green to bluish-green. |
| Flowers | Cedar trees produce small, inconspicuous flowers in the fall. Male flowers are catkin-like and release pollen, while female flowers are small cones that develop into the characteristic barrel-shaped seed cones. |
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
Cedar
Onion
🌱 Propagation — Comparing Plant Growth
Cedar
Methods: Seed, Cuttings (difficult)
Difficulty: Difficult
Tips: Seed propagation requires stratification. Cuttings are difficult and require rooting hormones and a controlled environment.
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
Cedar
True cedars are distinguished by their barrel-shaped cones and needle-like leaves arranged in spirals on long shoots and in dense clusters on short shoots. Their aromatic wood is highly valued for its insect-repelling properties.
- ✓ Provides shade and shelter for wildlife
- ✓ Enhances property value and curb appeal
- ✓ Offers a sense of tranquility and connection to nature
- ✓ Aromatic wood provides a pleasant scent
- ✓ Long lifespan provides lasting beauty.
- ⚠️ Toxic to pets
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
Cedar
Onion
🌞 Light Requirements
Cedar
Full sun (at least 6 hours of direct sunlight per day)
Low light tolerant: ❌ No
Onion
Full sun (6-8 hours of direct sunlight daily)
Low light tolerant: ❌ No
💧 Watering Needs
Cedar
Water deeply when the topsoil feels dry to the touch. Ensure proper drainage to prevent root rot. Overwatering can lead to fungal diseases, while underwatering can cause needle drop and stress.
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
Cedar
Temperature: 10-24°C
Humidity: 30-50%
Onion
Temperature: 13-24°C
Humidity: 40-60%
🤔 Which Plant Is Right For You?
Cedar
Cedrus spp.Landscapers and gardeners with outdoor space suitable for large trees.
✅ Choose This Plant If...
- You have ample outdoor space for a large tree
- You appreciate the aromatic scent of cedarwood
- You want a majestic and long-lived tree in your landscape
- You need a windbreak or privacy screen
- You are experienced with tree care and maintenance.
❌ Skip This Plant If...
- You live in an apartment or have limited space
- You are looking for an easy-to-care-for indoor plant
- You have pets that may ingest the plant
- You live in a region with unsuitable climate for cedar trees.
Onion
Allium cepaGardeners 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.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Cedar needs full sun (at least 6 hours of direct sunlight per day), while Onion prefers full sun (6-8 hours of direct sunlight daily).
Cedar has moderate growth, while Onion grows moderate.
💡 Pro Tips For Comparing These Plants
Cedar Care Tips
Cedars are primarily outdoor trees and are extremely challenging to grow indoors. They require full sun, well-draining soil, and proper humidity levels, which are difficult to replicate indoors. Indoor cultivation is generally not recommended.
- Ensure proper drainage to prevent root rot
- Water deeply but infrequently, allowing the soil to dry out slightly between waterings
- Protect young trees from harsh winter winds and frost
- Monitor for pests and diseases regularly
- Prune annually to remove dead or damaged branches and maintain shape.
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.
⚠️ Common Problems & Solutions — Plant Care Comparison
Cedar
Onion
❓ Frequently Asked Questions — Comparing These Plants
Cedar
What are the light requirements for Cedar?
Indoor cedars thrive in bright, indirect light. Placing them near an east- or west-facing window is usually ideal. Avoid direct sunlight, especially during the hottest part of the day, as it can burn the delicate needles. Insufficient light can lead to leggy growth and yellowing foliage. If you don’t have access to sufficient natural light, consider supplementing with a grow light. Rotate your cedar regularly to ensure all sides receive adequate light. During the winter months, when sunlight is less intense, you may need to move your cedar closer to a window or increase the amount of supplemental light. Pay close attention to the plant’s growth and adjust its position accordingly.
How do I care for Cedar?
Indoor cedar trees require bright, indirect light; avoid direct sunlight, which can scorch the foliage. Water thoroughly when the top inch of soil feels dry, ensuring good drainage to prevent root rot. Use a well-draining potting mix formulated for conifers or evergreens. Maintain moderate humidity, especially during dry winter months. Fertilize sparingly, only during the growing season (spring and summer), with a balanced liquid fertilizer diluted to half strength. Prune regularly to maintain the desired shape and remove any dead or yellowing foliage. Repot every 2-3 years, or when the plant becomes root-bound, into a slightly larger pot. Ensure adequate air circulation to prevent fungal diseases. Monitor for pests such as spider mites or scale and treat promptly. Provide stable temperatures, avoiding drastic fluctuations. Rotate the plant regularly to ensure even growth on all sides.
How do I propagate Cedar?
Cedar can be propagated through stem cuttings or air layering. For stem cuttings, take 4-6 inch cuttings from new growth in spring or early summer. Remove the lower needles and dip the cut end in rooting hormone. Plant the cutting in a well-draining potting mix and keep it moist and humid. Rooting can take several weeks to months. For air layering, make a small incision in a branch, apply rooting hormone, and wrap the incision with moist sphagnum moss. Cover the moss with plastic wrap and secure it with tape. Once roots have formed, cut the branch below the roots and pot it up. Both methods require patience and careful monitoring. Maintain consistent moisture and humidity for successful propagation. Choose healthy, vigorous branches for the best results.
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: April 26, 2026 — Plant care data reviewed and verified by our editorial team.