There are bad watermelon companion plants that can seriously endanger your crops! If you are a newbie gardener looking for tips on how to ensure your watermelon crop is always growing strong, you’ve come to the right place!

8 Bad Watermelon Companion Plants

In this article, we’ll talk about the age-old companion planting technique and the good and bad plant companions to avoid or grow. We’ll also share our top tips for avoiding bad companion plants, as well as crop rotating techniques to help you get the most out of your garden.

Bad Watermelon Companion Plants List- The Most Dangerous Ones

Companion planting is an ancient gardening technique that has been around for centuries. It involves growing certain plants together in close proximity in order to maximize their growth and yield.

This is because certain plants can provide nutrients and beneficial microorganisms to each other and ward off pests. It’s important to know which plants are good and bad companions for your watermelon crop. Let’s see some you should definitely avoid!

1. Pole Beans And Bush Beans

Pole And Bush Beans tend to attract dangerous pests

Growing season Spring to early Summer
Distinguish characteristics 
  • Tall and low growing
  • Green pods
  • Fleshy leaves
Specific needs
  • moist but well-drained soil
  • Warm soil temperatures
Common pests 
  • Slugs
  • Snails 
  • Beetles, mites, and aphids

Pole beans are annual herbaceous plants that are known for their edible bean pods. The leaves of these beans are often used as a salad vegetable. All beans are members of the legume family called Fabaceae.

Bush Beans are very similar to pole ones, except they will grow on short and bushy plants. The plants won’t grow more than two feet tall, and some consider them to be good companion plants since they add nutrients to the soil. But let us convince you otherwise!

The soil needs some nitrogen to produce healthy plants and crops, which is why most gardeners will use them to help other crops.

However, beans can cast a shadow over your ground layer plants and prevent the sunlight from reaching them. This especially goes for your poled beans — you can unconsciously create a shadowy screen that can influence the growth of watermelons.

Furthermore, beans tend to attract dangerous pests, such as melon aphids which will attack your watermelon and cause serious harm to your crops. We definitely recommend other methods of adding nutrients.

2. Cucumbers

avoid growing Cucumbers with watermelon

Growing season Summer to Fall
Distinguish characteristics 
  • Succulent stem
  • Vining plant
  • Juicy and crunchy fruit
Specific needs
  • moist but well-drained soil
  • Ph of 6.0 to 6.5
Common pests 
  • Leaf rot, belly rot, mildew
  • Beetles, mites and aphids

Cucumbers are annual vine plants that are grown for their crispy and delicious fruits, typically eaten pickled or fresh. Cucumbers are fairly easy to grow and are prolific growers in many gardens across the world!

Although cucumbers are close relative to watermelons, you should avoid growing them together with the watermelon. This is because they attract similar kinds of pests, which will almost certainly double your chances of your crops getting under attack.

Moreover, both plants need plenty of room to grow and will compete for space in order to vine freely and grow healthy!

Being compatible, if planted together, these plants can cross-pollinate and create some unwanted hybrid species.

3. Zucchini

Keep zucchini as far as possible from your watermelon

Growing season Summer to Fall
Distinguish characteristics 
  • Leaves with prickly hairs
  • Bushy, non-vining plant
  • Juicy and crunchy fruit
Specific needs
  • moist but well-drained soil
  • Ph of 6.0 to 6.5
Common pests 
  • Leaf blight and spot, mildew
  • Cucumber beetles and aphids

Zucchini is another popular plant grown for its edible fruit, essential in many cuisines around the world. These plants can reach around two feet high and about three feet wide.

Some vining zucchini varieties can spread up to 10 feet wide! Their beautiful flowers resemble those of pumpkins’.

Keep zucchini as far as possible from your watermelon plants, as the two will battle for space in your garden!

Furthermore, zucchini will attract pests like the cucumber beetle, which will gladly spread to the watermelon vines.

4. Pumpkins

Pumpkins and watermelon battle for their patch of the garden

Growing season Summer to Fall
Distinguish characteristics 
  • Broad leaves
  • vining plant
  • Thick orange fruit
Specific needs
  • Sandy soils and organic matter
  • Moist and well drained, mulched growing surface
Common pests 
  • Powdery mildew, stem blight
  • Cucumber beetles and pickle worms, spider mites

Pumpkins are large nutritious vegetables grown for their large fruits appreciated in the autumn! This plant can cover large areas with its leaves which makes it great natural mulch insulation.

This makes it an ideal companion planting with corn, peas, and radishes. However, you may want to keep it away from your watermelons.

Some pumpkin growers claim that pumpkins will do just fine near watermelons, but both crops will battle for their patch of the garden.

Both plants are also heavy feeders, and they should be kept apart as they will require lots of nutrients and will steal from each other!

Pumpkins and watermelons are from the same family but won’t cross-pollinate as they aren’t compatible.

5. Potatoes

potato plant needs enough space to spread

Growing season April to June
Distinguish characteristics 
  • Spirally arranged
  • Compound leaves
  • Purple flowers, with yellow stamens
Specific needs
  • moist but well-drained, sandy soil
  • Ph of 6.0 to 6.5
Common pests 
  • Common scab, early blight
  • Grubs, weevils, wireworms

A staple of the human diet, potatoes are a cold-season vegetable used in cuisines worldwide. They are grown for their nutritious and starchy tubers.

There are many varieties of potatoes developed from their early discovery by the Spanish conquerors. But why are they such a bad side crop for watermelons?

This potato plant needs enough space to spread its vines, therefore causing both the potato and the watermelon to compete for space.

If you plan on companion planting potatoes with watermelons, you should plan the sawing in order to have your potatoes out of the ground before your watermelon starts growing.

Another worrying fact is that potatoes can attract cotton or melon aphids which have the potential to cause damage to your watermelon plants.

6. Tomatoes

Tomatoes attract certain aphids

Growing season April to July
Distinguish characteristics 
  • Tall growing
  • Heavily branched
  • Hairy odorous leaves
Specific needs
  • moist but well-drained, sandy soil
  • Full sun
  • Ph of 6.0 to 6.5
Common pests 
  • Black mold, powdery mildew
  • Aphids, budworm, caterpillars

Tomato plants are tender garden perennials grown in temperate climates as annuals. Easy and prolific growers, tomato plants are the most widely grown garden tenants.

As with potatoes, there are tons of varieties you can grow depending on your taste. However, tomatoes can pose a danger when grown with watermelons.

Tomato plants, attract certain aphids that can wreak havoc on your watermelons. These plants need space to grow too, and can shade your watermelon plants disrupting the light from reaching your watermelon vines.

7. Asters And Roses

Asters And Roses cause significant damage to watermelon

Growing season May to Autumn
Distinguish characteristics 
  • Erect Shrubs
  • Thorny stems
  • Compound leaves
Specific needs
  • moist but well-drained, sandy soil
  • Full sun and partial shade
Common pests 
  • Black mold, powdery mildew, blight
  • Aphids, red spider mites, caterpillars

Asters are beautiful garden plants that bear sprays of large colorful flowers, some reaching three inches across with broad petals around golden disc centers.

They’re blooming for weeks between early and mid-autumn and are incredibly easy to grow. As long as they aren’t close to watermelons!

The same goes for your roses. Roses are one of the most appreciated garden flowering plants, noted for their luscious and big blooms coming in a variety of colors.

Roses have a pleasant smell and are hardy and vigorous shrubs that perform well in most climates.

Flowers that are members of the aster family catch the attention of heaps of several aphid species.

If planted close to the watermelon plant, they can cause significant damage to your watermelon plants.

The aphids can easily fly over from rose flowers onto those watermelons and enjoy their feast, leaving you with no feast of your own!

8. Brussel Sprouts

Brussel sprouts attract aphids

Growing season April to July
Distinguish characteristics 
  • Long smooth, leathery leaves
  • Sprouts forming at the base
Specific needs
  • moist but well-drained, sandy soil
  • Full sun
  • Ph of 6.0 to 6.5
Common pests 
  • Leaf spot, black rot, downy mildew
  • Aphids, cutworms, cabbage loopers

Brussel sprouts are a variety of cabbage from the Brassicae family and are grown for their cute, small, and green buds which look like small cabbages! The brussel sprout plant has long, smooth, and dark green leaves which are growing in an alternating fashion on the stem. 

The very method of companion planting is to plant species that can benefit from one another, often to ward off pests and to make the soil more nutritious. Brussel sprouts tend to be very demanding feeders despite their size and can struggle for nutrients that will get eaten by the watermelon. 

Brussel sprouts attract aphids known for their appetite for watermelon flowers and leaves, so this companionship is a no-go!


Companion planting is a great way to maximize the productivity of your vegetable garden. However, it’s important to be aware of the good and bad watermelon company plants, as some can be detrimental to your watermelon health.

Let’s reiterate some of the points mentioned in this article!

  • To ensure your watermelon crop is always growing strong, avoid planting any kind of beans, pumpkins, potatoes, brussels sprouts, or tomatoes near your watermelons.
  • Additionally, make sure to practice rotating your crops each year to further ensure your garden’s health.
  • It’s a good idea to grow your watermelons next to herbs that can ward off pests and insects, such as garlic, basil, dill, or radishes.

Follow these tips, and you’ll be sure to have a bountiful watermelon crop year after year!

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