8 Plants to Plant With Onions - Backyard Boss
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8 Plants to Plant With Onions

Onions are a staple in many kitchens and gardens, but did you know that certain plants grow better when planted near them? Companion planting is a gardening technique where different plants are grown together for mutual benefit. Onions, for example, are known for their strong odor, which repels pests and can enhance the growth of other plants.

Below you will find the best companion plants for onions and learn why these companionships will benefit both parties. From herbs to vegetables, these plants will make your garden healthy, productive, and, most importantly, pest-free

What to Keep in Mind When Planting Near Onions

close up image of onion bulbs poking through the ground with tall green leaves above them
Image credits: Maarten van den Heuvel via Unsplash

When planting crops near onions, consider several factors to guarantee a thriving garden. Firstly, be aware of the growth habit and mature height of both plants, and understand each plant’s nutrient needs, as some crops may deplete the soil of specific nutrients, affecting the growth of their neighbors.

Take into account also proper watering, as over- or under-watering one crop can impact the health of the other and the sunlight requirements, as plants have varying needs for sun exposure.

By considering these factors, you can cultivate a productive and harmonious garden with healthy, thriving plants, where the onions can enhance the growth of other crops and act as natural pest deterrents.

Best Companion Plants for Onions


tomatoes ripening on a truss on a tomato plant, variety Sungold
Image credits: AngieC333 via Shutterstock

Planting tomatoes near onions provides several benefits. Onions emit a strong odor that deters pests such as aphids and Japanese beetles from attacking the tomatoes. Plus, they enrich the soil with essential nutrients, benefiting the growth and health of the tomatoes and enhancing their flavor.


Growing beets
Image credits: Denis Shitikoff via Shutterstock

Growing beets near onions is a winning combination for your garden! A strong smell of onion keeps pests away from the beets, as well as prevents them from fungal infection, ensuring a healthy crop. Plus, by taking up different levels of soil, the roots of onions and beets don’t compete for essential nutrients.


small lettuce
Image Credits: Diane Helentjaris via Unsplash

Planting onions and lettuce together can result in a mutually beneficial garden. The roots of these two crops occupy different depths in the soil, allowing them to access sources of nutrients without any competition, and the growth of onion bulbs is not hindered by lettuce as it has shallow roots. In addition, the strong aroma of onions acts as a natural deterrent, keeping pests from munching on your lettuce.


Harvesting carrots
Image credits: Jonathan Kemper via Unsplash

Carrots are another great companion for your onions. First, onions can shield carrots from carrot flies, while carrots deter onion flies. Both plants have different root structures and nutrient requirements, meaning they will not compete for nutrients or space. Plus, the growth of carrots, which require only a small amount of nitrogen, won’t be affected by the presence of onions, which have a high nitrogen demand.


Cabbage in sunlight
Image credits: Clint McKoy via Unsplash

Growing cabbage and onions together has numerous benefits for both the plants and the gardener. The strong fragrance of onions repels pests such as aphids, cabbage worms, or cabbage loopers that may damage the cabbages. Additionally, intercropping cabbage and onions reduces the need for extra space and conserves resources like water and soil nutrients.


Fresh leaves of young parsley, green vegetable.
Image credits: k_samurkas via Shutterstock

Parsley and onions are easy to grow, low maintenance, and thrive in similar soil and climate conditions. It means that they can save space and reduce the need for additional resources like water, making them a sustainable and efficient choice for the garden. Furthermore, the combination of parsley and onions can offer a variety of flavors and aromas to enhance the taste of dishes.


Strawberry hunting
Image credits: MaMi via Shutterstock

With proper care, growing strawberries and onions together can provide a tasty and nutritious harvest that is sure to delight. It’s because onions keep aphids away that tend to invade strawberry leaves. Plus, strawberries and onions are easy to grow and require minimal maintenance, making them a perfect choice for beginner gardeners.


broccoli growing
Image credits: Hans Ripa via Unsplash

By planting these two crops together, you can create a well-rounded and productive garden space that supports the growth and health of both broccoli and onions. Broccoli, as a member of the cabbage family, experiences similar benefits from planting with onions as their cousin crops, such as cabbage. By having onions as companions, broccoli can avoid damage from pests.

To Sum Up

Incorporating the right companion plants in your garden can elevate the growth and health of your onions to new heights. By pairing them with their ideal neighbors, you can reap numerous benefits, from deterring harmful pests to enhancing soil quality. The eight companion plants in this article complement your onions in ways that will leave you amazed at their harmonious coexistence. They bring diversity to your garden and create a thriving ecosystem that supports the growth and health of all the plants in your space.

Which other companion plants for onions do you know? Comment below, and as always, please share!