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4 Vegetable Plants To Never Grow Near Tomatoes!

There are certainly quite a few articles dedicated to the best plants to grow near tomatoes to help with pollination and pest control – but did you know there are four vegetable plants you should never plant near your tomatoes?

Growing tomatoes can be incredibly rewarding, but ensuring a healthy and bountiful harvest requires more than just proper watering and sunlight. While many plants make excellent companions for tomatoes (marigolds and basil are two great examples), there are others that should be kept far away.

The Dangers Of Poor Companion Planting

As it turns out, some plants do more harm than good when planted near tomatoes. Some can attract harmful pests that feed on tomato plants. Meanwhile, others deplete essential nutrients from the soil. Nutrients that if missing, can reduce tomato yields, or even worse, put the plant’s health in jeopardy.

plants to never grow near tomatoes
Tomatoes and cucumbers might go well in dishes – but they don’t help each other when they are close in a garden setting.

But it doesn’t stop there. Bad companion planting can also encourage diseases by creating the right conditions for fungal or bacterial infections. And last but not least, some plant varieties that grow too close to tomatoes can compete for space and sunlight, ultimately stunting a tomato plant’s growth and production levels.

So which vegetables are the worst offenders? Here is a list of four plants that you need to distance from your tomato plants – and why!

4 Vegetable Plants To Never Grow Near Tomatoes

1. Cucumbers

Cucumbers and tomatoes may seem like ideal garden neighbors, especially when you consider how well they can go together in dishes in the kitchen – but they actually cause several problems for one another when planted together.

One of the biggest issues is with disease. Cucumbers and tomatoes are both prone to fungal diseases like powdery mildew and downy mildew. And planting them together increases the risk of spreading these infections to each other, especially in humid conditions.

But cucumbers can also rob tomatoes of much needed moisture. Cucumbers require a lot of water to grow. Tomatoes, on the other hand, prefer a more controlled watering schedule. When they grow together, cucumber plants can soak up a large majority of available moisture, leaving tomatoes struggling.

mildew
Cucumber plants can often harbor mold and mildew. When growing near tomatoes, they can transfer that quite easily.

Last but not least, cucumbers bring in quite a few pests that can then affect tomato plants. Both cucumbers and tomatoes attract pests like aphids, whiteflies, and cucumber beetles. Planting them together creates a magnet for these harmful insects, making it harder to protect your plants.

In an ideal setting, try to keep your tomato plants at least 15 feet away from any cucumber plant. And if you can go farther apart – all the better!

2. Cabbage

Cabbage, (along with fellow family members broccoli, cauliflower, and Brussels sprouts), is another vegetable plant that should never grow near tomatoes.

For starters, cabbage is a heavy feeder, meaning it requires a large amount of nutrients from the soil to grow well. Tomatoes also need a lot of nutrients, especially nitrogen and phosphorus. Unfortunately, planting them together can lead to nutrient deficiencies and stunted growth for both.

But cabbage also is an issue when it comes to space. Cabbage plants spread wide and far, and have dense foliage. This can shade tomato plants and prevent them from getting the sunlight they need to produce fruit.

vegetable plants  - tomato plants
Cabbage can attract large populations of aphids. Aphids that will then gladly jump onto nearby tomato plants. Not only can aphids harm plant growth – they can also bring on disease.

Last but not least, cabbage can attract aphids and other pests that love tomato plants too. Planting them nearby can mean big pest issues for your tomato plants.

3. Sweet Corn

Sweet corn and tomatoes are both popular summer vegetables, but they should never be planted near each other due to their impact on pest populations and competition for nutrients in the ground.

Corn attracts a lot of pests, most notably earworms (also known as tomato fruitworms) – which are the same pests that love to feast on tomatoes. Planting them together makes it easier for these pests to spread from one crop to the other, and doubling if not tripling their population.

Corn, like tomatoes, is also a heavy feeder that rapidly absorbs nutrients from the soil. Especially when it comes to the all important nutrient of nitrogen, which tomatoes need for strong leaf and plant growth. Growing the two in the same area can result in the soil just not having enough power for both crops.

Last but not least, there is a shading issue. Corn grows much taller than tomato plants and can block the sunlight that tomatoes need to produce and ripen their fruit. Reduced sunlight can lead to lower yields and far longer ripening times.

4. Why To Never Plant Carrots With Tomatoes

While carrots may seem harmless, they are not the best companion for tomatoes due to their different growth requirements and impact on the soil.

Carrots and tomatoes both have extensive root systems. Carrots need loose, aerated soil to grow properly. But tomato roots can become large and fibrous, making it hard for carrots to develop properly.

Carrots don’t deplete nutrients as aggressively as cabbage or corn, but they still compete for important nutrients. Especially when it comes to phosphorus and potassium, which are important for tomato fruit production.

When harvesting carrots, the process of pulling them up can also disturb the roots of nearby tomato plants, potentially leading to stress or damage to the tomato’s root system.

The Best Alternatives To Plant With Tomatoes

If you want to ensure a healthy tomato crop and use companion planting to its full potential, there are a couple of great companion planting partners – basil and marigolds!

One thing is for sure, companion planting with the right plants can make a huge difference. And, by keeping the plants you should never grow with tomatoes far away, you’ll reduce the risk of pest infestations, nutrient competition and disease. Together – it can lead to a healthier, more productive garden.

Here is to growing great tomatoes – and a great garden this year!

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