Tomatoes are one of those vegetables that anyone can plant with ease and provide several health benefits. Some of these benefits include reducing the risk of cancer and diseases related to the heart as they are rich in antioxidants, Vitamin C, and Vitamin E.
However, apart from the benefits, growing tomatoes could result in some potential problems as well. For example, fungal diseases, invasion of aphids, along with early and late blight.
To avoid these pesky problems and gain full advantage of growing tomatoes, you should plant them with their best companion plants. Companion Planting might be mutually beneficial when planted close as they help in pollination and reduce diseases among plants.
Before getting to the best and worst companion plants for tomatoes, let us understand exactly companion planting and companion plants.
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What Is Companion Planting?
The process of growing two or more companion plants near each other is known as Companion Planting. It results in several benefits such as better growth, repelling unwanted insects, attracting insects that feed on pests, and an overall better yield.
Companion Plants refer to the combination of plants that, when planted together, result in better growth. This can be due to several factors such as their common requirement of certain nutrients, pest deterring abilities, along similar growing and harvesting traits.
Now that you’re aware of the concept of companion planting, you should read further to know about the best and worst companion plants that you should and shouldn’t plant with your tomatoes, respectively.
Best Companion Plants For Tomatoes
Companion Plants for tomatoes are those plants that help in improving the overall health of tomatoes by deterring various garden pests. Not only do they benefit the tomatoes, but they would also make your garden look more diverse.
Some of the most prominent companion plants for tomatoes are Asparagus, beans, bee balm, borage, garlic, lettuce, and most importantly, marigolds and carrots. Let us now understand how these plants can help tomatoes.
The strong smell of Marigolds, along with its beautiful yellow-gold color, makes them a good companion that can be planted alongside tomatoes. Out of all the different types of Marigolds, it’s suggested that you should plant French Marigold.
Its strong smell has the ability to repel various general insect pests such as aphids, thrips, whiteflies, slugs, tomato hornworms. Apart from these, its scent confuses other insects and increases the safety of other companion plants as well.
Additionally, if you would pot marigold between tomatoes, it would prevent them from the nematodes, parasites that feed on the tomato’s root system and cause root-knot and damage the entire plant.
It would be best if you planted carrots and tomatoes together, at the same time, as they are considered to be the best neighbor companions. The root of carrots helps break the soil around them, allowing more air and water to reach the tomatoes.
Most importantly, the harvesting time of the companion plant time is pretty much compatible with that of the tomato plants, and it would help you save a lot of space in your garden.
If you want to repel pests in your garden and enhance tomatoes’ flavor, you should plant Basil near them. The aromatic herb is one of the best companion plants for tomatoes on and off the ground as it easily repels aphids, spider mites, mosquitoes, and whiteflies.
It repels insects such as whiteflies, mosquitoes, houseflies, aphids, and asparagus beetles, that harm tomatoes. Moreover, Basil attracts beneficial insects like bees and hence, improves pollination and increases your garden diversity.
You should plant three basils around every single potato to make the best of all the benefits mentioned above.
In addition to it, growing tomatoes borage would improve the growth and flavor of the tomatoes well together. The companion plant will also help repair pests like cabbage worms, making it suitable to protect cabbage planted in your garden.
4. Lettuce and Spinach
Annual green vegetables like lettuce and spinach go well together with tomatoes as they help in its growth and, at the same time, save a lot of space. Just like carrots, the leaves of the vegetable are ready for harvest as soon as the tomatoes are planted.
The fact that the leafy vegetable is full-grown provides shade to tomatoes, makes it one of the best companions for tomatoes. The shade helps the tomato plants to grow as it blocks excess sunlight and keeps the soil cool and moist.
In addition to that, lettuce helps in stopping unwanted weeds from growing that steal away all the nutrients and flavor from the tomatoes.
If you want to deter pests like spider mites from your tomatoes, you should definitely plant Garlic alongside them. Its pungent and robust odor can deter pests such as flea beetles, whiteflies, cabbage worms, moths, ants, and spider mites from your tomatoes or garden, in general.
However, if you don’t want to plant Garlic in your garden, you can make an insecticide out of a couple of garlic cloves around the tomato plants. You can spray the insecticide around the tomatoes as it would protect the plant and soil from blight.
Nasturtium is a natural pest-repelling flower as it releases bitter oil with a hint of pepper. The oil repels squash bugs, beetles, and whiteflies. In addition to these pests, the flower acts as a trap crop for aphids.
However, it would be best if you did not plant this edible and pretty flower too close to the tomato plants. This is because they overgrow and might take them over along with the tomato and other plants.
Mutually Beneficial Companion For Tomatoes: Asparagus
Apart from the plants mentioned above, you can also plant mutually beneficial companion plants like Asparagus near the tomato plants. It can quickly get rid of root-knot nematodes.
At the same time, tomatoes help Asparagus grow by repelling asparagus beetles by releasing a chemical known as solanine.
Worst Companion Plants For Tomatoes
While there are various tomato companion plants, there is a whole separate category of plants that tomatoes repel. For example, cabbage, corn, Dill, potatoes, peppers, or walnuts.
Let us now understand why you should never plant some of these plants with tomatoes.
You should never grow two or more nightshade vegetables together to increase their chances of contracting a similar disease. For example, all nightshade plants are prone to early and late blight caused by the fungus Phytophthora, which can quickly spread across other plants.
The blight would result in plant tissues’ death that causes the leaves to turn brown and wither. Therefore, since tomatoes, potatoes, and eggplants all belong to the same nightshade group, growing them together would result in the soil losing all its nutrients.
Cabbage and other kinds of Brassicas like broccoli, kale, Brussel sprouts, and kale should be planted away from the tomato plants. The vegetable repels tomato by inhibiting its growth by clashing with one another for extra space for its root.
Just like tomatoes, it requires a proper place in the soil for their roots to grow. However, cabbage tends to overpower tomatoes and takes the majority of the space. This results in small, underdeveloped tomatoes that lack flavor.
On the other hand, if, in rare circumstances, the tomato can overpower, it would block the growth of cabbage because of its deep roots and tall height.
Unlike herbs like Basil and parsley, Fennel is one of the worst companions for tomato plants. It repels tomato by preventing from growing by secreting a particular chemical, the reason behind its pleasant smell and flavor.
The chemical affects not only the growth of tomatoes but other plants as well. Therefore, if you want to grow fennels in your garden, you would need to dedicate a separate space to them so that it doesn’t come in between other plants’ growth.
It would be best if you never plant tomatoes and corn together as they both have a tendency to attract their mutual enemy: tomato fruit worm or corn earworm, also known as the cotton bollworm.
If you pant both of these plants together, it will result in the creation of one of the most comfortable places for these pests. The pests would be able to target the plants quickly and destroy them. Moreover, they can also destroy the entire garden at a rapid rate.
It would also result in rotten tomatoes and a destroyed garden with other infected plants. This is because they would attract the pests, and they would spread quickly throughout the garden.
5. Black Walnuts
The deciduous tree is one of the worst plants that you could plant alongside tomatoes because of walnut wilt. They inhibit or stunt their growth by releasing a toxic chemical known as Juglone. The chemical is harmful to any vegetable belonging to the nightshade family and can cause walnut wilt in them.
So far, we have discussed the individual best as well as worst companions for tomatoes. In addition to them, some plants like Dill are both beneficial and troublesome for tomatoes.
Mutually Beneficial Companion For Tomatoes: Dill
As a young herb, Dill can help the tomato grow and improve its health by attracting beneficial insects such as ladybug larvae that feed on pests like tomato worms that are harmful to the tomato plants.
However, as Dill grows further into a mature herb, it can stunt tomatoes’ growth by releasing allelopathic chemicals that would deteriorate its root.
Therefore, it’s suggested that you shouldn’t plan it with tomatoes. If you’ve already planted them, you should harvest it before it matures and starts interfering with the growth of the tomato plant.
Companion Planting is a fantastic way to make sure that you’re able to grow multiple plants simultaneously and ensure that they get all things required for their proper growth.
So, if you want to plant healthy tomatoes in your garden, you should try to grow them alongside herbs and vegetables like basil, borage, beans, parsley, carrots, peas, chive, squash, bee balm, and most importantly, marigolds. Some of them repel harmful pests, while others ensure that they get enough space to grow.
Apart from this, it would be best if you never plant tomatoes with corn, walnuts, and other nightshade plants like potatoes and eggplants. These plants and vegetables interfere with tomatoes’ growth by either inviting pests or consuming their required space to grow.
James Fields is the founder of Gardener to Farmer. His passion for gardening goes back to his childhood days when he would visit his grandfather during the holidays and help him with the plants in the backyard. This has now translated to creating a dependable resource for gardening.