Onions are a great addition to any vegetable garden. They are easy to grow and very healthy. This article gives an overview of the plants that grow well with onions and those that don’t, as well as what you should think about when rotating crops with onions and an example planting plan for planting onions with other plants.
If you want to deter pests and increase yields in your vegetable garden, consider planting onions and tomatoes together Known as companion planting, cultivating mutually beneficial vegetables side-by-side leverages their natural strengths.
Onions make great companions for tomatoes Their pungent scent drives away many insects that can damage tomato plants and fruits Plus, onions help improve soil nutrients to boost tomato growth.
Companion planting onions and tomatoes offers many advantages:
Onions Repel Harmful Tomato Pests
Onions contain sulfur compounds that give them their characteristic strong smell and taste. The same compounds that make us cry when chopping onions also repel several common tomato pests:
- Aphids
- Flea beetles
- Whiteflies
- Cutworms
- Rabbits
These insects and animals dislike the smell of onions. Planting onions around your tomatoes creates a living pest repellent.
Onions Enhance Tomato Flavor
In addition to repelling pests, onions can actually enhance the flavor of nearby tomatoes.
As onions grow, sulfur compounds are absorbed from the soil. These same compounds contribute to tomato taste.
Onions help tomatoes develop more savory, rich flavors. You’ll notice the difference when harvesting crops from companion planted plants!
Onions Loosen and Aerate Soil
With their shallow, fibrous roots, onions help break up and aerate heavy garden soils. This benefits neighboring tomato plants that produce deep roots.
Loosened soil enables tomato roots to spread easily underground. Improved drainage and oxygen circulation supports better root development.
Onions Add Nutrients to Boost Tomato Growth
Onions absorb sulfur from the soil, but they also accumulate other nutrients:
- Calcium
- Potassium
- Phosphorous
- Magnesium
- Copper
As onions decompose over time, these nutrients are released back into the earth. Tomato plants grown nearby can take advantage of this extra nutritional boost.
Optimal Growing Conditions for Onions and Tomatoes
When grown as companion plants, onions and tomatoes share these ideal growing conditions:
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Sunlight: At least 6-8 hours of full sun daily.
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Soil: Neutral pH, fertile loam amended with compost.
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Water: Consistent moisture, about 1 inch per week.
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Temperature: Around 70-80°F during the day.
Match these conditions in your garden and both veggies will thrive!
How to Grow Onions and Tomatoes Together
Follow these tips for success with companion planting onions and tomatoes:
Start Seeds or Buy Transplants
You can grow onions and tomatoes from seeds started indoors or purchase transplants. Fast-growing onion sets are also a planting option.
Allow Proper Spacing
Space tomato plants at least 2 feet apart; onions 4-6 inches apart. Alternate rows with 1-2 feet between plants.
Plant Onions First
Onions mature faster, so plant onions a few weeks before transplanting tomatoes outdoors.
Site in Full Sun
Choose a spot that receives at least 6 hours of direct sunlight daily.
Prepare Soil
Enrich soil with aged compost or manure before planting. Mix in balanced organic fertilizer.
Water and Mulch
Water transplants well and add 2-3 inches of mulch to retain moisture. Replenish mulch as needed.
With good planning, your onion and tomato companion plants will soon start benefiting each other!
Maintaining Onion and Tomato Companion Plantings
Keep your onions and tomatoes healthy with these care tips:
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Water deeply 1-2 times per week, providing about 1 inch total.
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Fertilize onions and tomatoes every 2-3 weeks during the growing season.
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Weed weekly to prevent competition for water and nutrients.
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Use row covers or crop cages to protect plants from pests.
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Rotate crops each year to prevent disease buildup in soil.
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Prune damaged tomato vines; remove spent onion plants.
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Harvest onions when tops fall over and dry; pick tomatoes when fully colored.
With attentive care, you’ll enjoy a bountiful harvest of robust onions and flavorful tomatoes!
Enjoying the Fruits of Companion Planting
Growing onions and tomatoes together results in a tasty harvest. Here are some ways to use your homegrown veggies:
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Add sliced onions and tomatoes to sandwiches, burgers, and wraps.
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Toss chopped onion and halved cherry tomatoes into green salads.
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Fry onions in olive oil to caramelize; serve over fresh tomato sauce on pasta or pizza.
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Make homemade salsa with onions, tomatoes, cilantro, lime, and jalapeño.
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Grill kebabs alternating tomato, onion, zucchini, and meat pieces.
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Bake tomatoes stuffed with a mixture of onion, bread crumbs, Parmesan, and herbs.
With an abundance of fresh onions and tomatoes, get creative in the kitchen!
Companion planting mutually beneficial vegetables is an easy way to deter pests, increase yields, and maximize garden space. Onions and tomatoes make excellent planting partners. With some planning, you can leverage their complementary strengths to grow more of these kitchen staples.
Companion planting with onions: suitable neighbors
Companion planting with onions has many advantages. You improve your harvest as pests and diseases are kept away better. You also make more effective use of the space and nutrients in your bed. Companion planting can also improve the taste of your vegetables. Some plants, like garlic, can grow with onions. Some plants from the same family as the onions can grow with onions. However, some vegetables should not be grown alongside onions. You can read about which plants do well with onions and which should be planted somewhere else below.
Succession planting & crop rotation with onions
Succession planting and crop rotation are important concepts when it comes to growing vegetables. The soil stays healthy and pests and diseases are less likely to spread when crops are rotated and grown for a long enough time. Here are some tips for crop rotation and crop rotation with onions:
Good succession plan ensures that the soil in your garden is not depleted and remains healthy. In order to do this, you shouldn’t plant heavy feeders next to each other or in the same spot in the bed. Otherwise you will encourage diseases and pests and the growth of your plants will be inhibited.
You can plant or sow onions in the bed early in the year, so you might be able to grow fast-growing plants like lettuce, spinach, or radishes first. These crops have a short growing time and can be sown a little earlier, depending on the variety.
There are different crops that come after onions depending on whether they were grown from spring to summer or fall to spring. As catch crops, over-wintering crops like cabbages, lamb’s lettuce, or green manure can be grown in the summer on ions. If you chose to grow autumn onions, the bed will be free again in June. At that point, you can use it to grow already-grown plants like peppers, cucumbers, zucchini, pumpkin, tomatoes, or tomatoes.
If you grow onions in a bed one year, you shouldn’t grow onion plants or other allium plants there again the next year. You should take a cultivation break of 3 – 4 years. Otherwise you will encourage the colonization of pests or diseases.
Planting Onions With Tomatoes, Why ?
FAQ
What should you not plant near onions?
Can peppers and onions be planted together?
Can you plant onions and tomatoes together?
Companion planting onions and tomatoes together can attract beneficial insects, repel pests, and prevent diseases. This gardening companionship can enhance the flavor, yield, and quality of your tomatoes. Marigolds, garlic, basil, and lavender are among the best companions for onions and tomatoes.
Do you need a companion plant to plant onions and tomatoes?
Companion planting onions and tomatoes is surprisingly easy and will allow you to reap the bountiful rewards without a ton of work. You’ll need to have your tomato plants and onion seedlings on hand, as well as a nice sunny spot scoped out in your garden.
Can you grow tomatoes and onions in the same container?
By understanding the principles of companion planting and providing the necessary conditions, you can create a thriving and productive garden that showcases the harmonious relationship between these two versatile vegetables. Yes, you can grow tomatoes and onions in the same container, provided it is large enough to accommodate both plants.
Should you plant onions alongside tomatoes & peppers?
The advantages of planting onions alongside tomatoes and peppers are manifold. One significant benefit is their ability to deter pests that commonly affect these plants. Onions emit an odor that repels insects like aphids, onion flies, and nematodes which can damage or destroy tomato and pepper crops.
Should you add companion plants to a tomato garden?
Before adding companion plants, ensure they flourish in the same garden conditions as tomatoes: full sun and rich, well-drained soil. Enormously scented herbs may help repel insect pests, while flowers attract pollinators.
How far apart should tomatoes and onions be planted?
Tomatoes and onions have different watering and nutritional needs, so you’ll want to try to plant them in an orderly fashion, otherwise, they’ll start competing for food and possibly choke each other out. That’s why the recommended spacing is one to two feet between each plant, and growing them in alternating rows.