6 onion companion plants and what you should avoid

Table of Contents
Onion

Companion planting for onion is an experience-based observation developed over centuries. People have noticed that planting certain plants side by side has a positive effect on each other, increasing the quality and quantity of the harvest.

Companion planting is not set in stone and it is the least you can do for your plants. You can get the right care from the individual plant article. You can see the companion and the enemy plants of onion below.

Companion plants for onionEnemy plants of onion
ChamomileBeans
BeetrotAsparagus
StrawberryCommon sage
TomatoGarlic
PepperLeek
MintChives

Why does companion planting work?

Companion planting works due to several interconnected factors:

Pest Control: Certain plants emit natural chemicals or scents that repel pests, effectively acting as natural pest deterrents for nearby plants. This reduces the need for chemical pesticides and fosters a more balanced ecosystem.

Attracting Beneficial Insects: Some companion plants attract beneficial insects like ladybugs, hoverflies, and predatory wasps, which feed on common garden pests. This creates a natural form of pest control and helps maintain ecological balance.

Soil Improvement: Different plants have varying root structures and nutrient requirements. Companion planting can enhance soil health by reducing soil erosion, suppressing weeds, and improving nutrient uptake. For example, leguminous plants fix nitrogen in the soil, benefiting neighboring plants that require nitrogen for growth.

Competition Reduction: Companion planting can help reduce competition for resources such as water, sunlight, and nutrients by utilizing plants with complementary growth patterns and root structures. This allows for more efficient resource utilization and healthier plant growth.

Biodiversity and Resilience: Planting diverse species together increases biodiversity in the garden, which can enhance ecosystem resilience. A diverse ecosystem is better equipped to withstand pests, diseases, and environmental stresses compared to monocultures.

Maximizing Space: Companion planting allows gardeners to make the most of limited space by intercropping plants with different growth habits and maturity rates. This maximizes yield per square foot and promotes efficient land use.

Overall, companion planting capitalizes on the natural synergies between plant species, creating a thriving and sustainable garden ecosystem.

What are the companion plants of onion?

The following plants have positive effects on the growth of your onion. These plants can repel pests that damage your plants. These plants provide increased nutrition to the soil that your plants can use. Therefore, we recommend planting these plants next to your onion.

Onion

Chamomile

Chamomile thrives in diverse growing conditions. Flourishing in well-drained, loamy soil under gentle sunlight, it embodies adaptability and calmness. Consistent moisture and occasional pruning support lush growth and abundant flowering. Chamomile offers general benefits to neighboring plants by attracting beneficial insects, such as pollinators, and enhancing overall biodiversity.

Onion

Beetrot

Beetroots, celebrated for their earthy sweetness and nutrient-rich composition, thrive amidst fertile soil and ample sunlight. They prefer well-drained earth with a pH range of 6.0 to 7.0, ensuring optimal growth and development. Regular watering and loose soil encourage healthy root formation and vibrant foliage.

Onion

Strawberry

Strawberries grow in loamy soil with a pH range between 5.5 and 6.5. Full sunlight and consistent moisture nurture their delicate fruits and lush foliage. Strawberries provide invaluable benefits to neighboring plants by attracting pollinators, suppressing weed growth with their dense foliage.

Onion

Tomato

Tomatoes thrive in various soil conditions. Flourishing fertile soil with a pH range between 6.0 and 7.0. Full sunlight and consistent moisture nurture their sprawling vines and abundant fruiting. Tomatoes provide invaluable benefits to neighboring plants by attracting pollinators, suppressing weed growth with their dense foliage, and adding richness to culinary dishes.

Onion

Pepper

Peppers expand in diverse soil conditions. Flourishing in well-drained, loamy soil with a pH range between 6.0 and 7.0. Full sunlight and consistent moisture nurture their vibrant foliage and prolific fruiting. Peppers provide invaluable benefits to neighboring plants by deterring pests with their pungent compounds, attracting pollinators, and adding diversity to the garden landscape.

Onion

Mint

Mint thrives in various soil conditions. Flourishing in well-drained, moist soil with a pH range between 6.0 and 7.0. Partial shade and consistent moisture nurture its lush foliage and aromatic leaves. Mint provides invaluable benefits to neighboring plants by repelling pests, attracting beneficial insects, and promoting a sense of freshness in the garden.

Planting these plants next to onion has a huge negative effect on the development of your plant. Growing enemy plants can appeal detrimental insects, change the taste of the grown plant and even consuming all of the nutrients and water from your onion. Because of these negative effects, we don’t recomment growing the plants below next to your onion.

Onion

Beans

Beans are thriving in well-drained soil and basking in ample sunlight, these leguminous wonders enrich the soil with nitrogen, enhancing the vitality of their botanical companions. As stalwart providers of sustenance and greenery, beans epitomize the essence of garden bounty and vitality.

Onion

Asparagus

Asparagus, revered for its tender spears and nutritional prowess, stands as a stalwart sentinel in the realm of companion gardening. With a penchant for well-drained, sandy soil and ample sunlight, this perennial delight thrives in environments where winters are cold and summers are warm. As a symbol of grace and gastronomy, asparagus enriches both the palate and the garden landscape, embodying the essence of verdant vitality.

Onion

Common sage

Common Sage grows in diverse soil conditions. Flourishing in well-drained, sandy or loamy soil. Full sunlight and moderate moisture nurture its aromatic foliage and sturdy growth. Common Sage provides invaluable benefits to neighboring plants by repelling pests, attracting beneficial insects, and adding culinary richness to the garden.

Onion

Garlic

Garlic flourishes in well-drained, fertile soil with a pH range between 6.0 and 7.5, it embodies adaptability and strength. Adequate sunlight and consistent moisture support robust growth and bulb development. Garlic provides invaluable benefits to neighboring plants by deterring pests with its strong aroma and acting as a natural fungicide against soil-borne diseases.

Onion

Leek

Leek thrives in various soil conditions. Flourishing in well-drained, fertile soil with a pH range between 6.0 and 7.0. Partial shade and consistent moisture nurture its slender stalks and tender leaves. Leek provides invaluable benefits to neighboring plants by deterring pests with its pungent aroma and improving soil structure with its deep roots.

Onion

Chives

Chives thrive in well-drained, fertile soil enriched with compost, they embody adaptability and finesse. Adequate moisture and sunlight support lush growth and abundant foliage. Chives extend general benefits to neighboring plants by repelling pests and attracting beneficial insects, enhancing overall garden biodiversity.

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