Rhubarb: Good & Bad Companions For It In Your Garden

The reward of gardening rhubarb, the harvest, is the best part of growing it. Its fleshy stalks work wonders in meals, salads, and desserts. However, if you value the space in your garden or food forest and want to get the most from it, then rhubarb shouldn’t be the only plant there. The only problem is that some plants are incompatible with it. You’ll probably wonder which plants go well with rhubarb and the ones that don’t. 


Cauliflower, beans, kale, broccoli, and garlic are good companion plants for rhubarb. Meanwhile, melon, black walnut, cucumber, pumpkin, and dock do not go well with rhubarb in a garden or food forest.  

Do you want to discover why these plants don’t go well with rhubarb and the implications of planting them together? If yes, then please keep reading as I’ll be addressing this and more in this article.

What Effects Would Planting The Wrong Plants With Rhubarb Have On It?

You aren’t wrong if you feel that mono-cropping with rhubarb is not the best permaculture practice. And you could have more healthy crops at harvest time if it isn’t the only plant in your garden. Nevertheless, when trying to diversify your garden, you might end up damaging your rhubarb. 

So it would be best to know the potential consequences of planting rhubarb with the wrong plants. Below are some negative effects associated with planting rhubarb with incompatible plants.

  1. Pest attack:  Certain pests are attracted to some plants. Over time, some of these plants have adapted to these pests and have undergone modifications to resist these attacks. So, they can suffer attacks without substantial loss in yield. Nevertheless, most of them still suffer substantial damage from these pests. 

Even worse is when these pests start targeting plants that they normally don’t attack. They would drastically affect the performance of the plants and decrease their yield. And planting the usually targeted plants with other plants makes them targets. 

Sadly, if you cannot control these pests, then planting their favorite crops with your rhubarb is a bad idea.

  1. Competition for soil nutrients: One of the most important things plants need for growth is nutrients. Mineral nutrients in the soil are crucial to plants, but sadly, they can be exhausted. As a result, some plants have modified roots that grow deeper to tap these nutrients as they slowly deplete further down the soil. 

However, some plants with even long roots perform poorly when planted with this kind of plant. Although rhubarb’s roots are relatively long, some plants with stronger roots can pose competition. It would be best if you avoided planting these with rhubarb.

  1. Allelopathy: Allelopathy is a phenomenon where a plant produces and releases biochemical substances that impairs the growth, development, reproduction, and even taste of other plants. Allelopathic plants do this to discourage plants from growing in their vicinity. So, they alone will have full access to the nutrients. 

If you plant an allelopathic plant along with your rhubarb, it will end up reducing its yield. Furthermore, it would also change its taste.

Rhubarb companion planting

What Are The Bad Companion Plants For Rhubarb?

Moving on, let’s find out exactly which plants aren’t good together with rhubarb and why they aren’t. Here are some plants that are incompatible with rhubarb

  1. Melon: Over the years, melon has become one of many gardeners’ favorite crops. This popularity is mostly because of the ground cover its leaves provide. Nevertheless, melon doesn’t go quite well with rhubarb in a garden. 

Melon crops are highly competitive when it comes to sunlight intake. The reason is that they require lots of sunlight to grow. If you plant them with rhubarb, and they aren’t getting enough light, they will exhibit phototropism.

The melon’s vines would wrap around your rhubarb and spread its leaves above it. But, of course, this would mean that your rhubarb won’t get enough sunlight in the process.

  1. Black Walnut: Although rhubarb makes a wonderful living mulch around many trees, it isn’t a good combination with black walnut. These trees are allelopathic because of the chemical produced by the tree called juglone, it can inhibit the growth of your rhubarb plant.
  1. Cucumber: Cucumbers are very competitive when it comes to soil nutrients. They will go to great extents to ensure that they get the right amount, regardless of the crop you plant beside them. And your rhubarb may not survive this competition. This competition would lead to its poor yield.
  1. Pumpkin: Pumpkin is a cousin to the melon. It’s, therefore, no surprise that it has the same problem with it. The phototropic ability of the pumpkin may end up being of more harm to your rhubarb than good.
  1. Dock: Although dock is a great crop, it doesn’t go well with rhubarb in the same soil. It attracts bugs to the garden, which could end up negatively affecting your rhubarb.

What Are Good Companion Plants For Rhubarb?

While some plants don’t go well with rhubarb, others do. And they even come with some benefits. Below are some plants that make great combinations with rhubarb.

  1. Cauliflower: Cauliflower belongs to the brassica family — a group of cruciferous plants. So, it naturally goes well with rhubarb without causing it any harm. Furthermore, it benefits from rhubarb’s ability to deter whiteflies.
  1. Beans: Beans are legumes that contain nodules in their roots which release nitrogen into the soil. Nitrogen is a key nutrient for rhubarb growth, so this nitrogen release is critical for its growth.

Furthermore, the oxalic content of rhubarb is a natural repellent to black fly aphids. Beans usually suffer from their infestation, so this is a win-win situation for both plants.

Also, beans provide good ground cover and help to prevent water loss from evaporation.

  1. Kale: Kale is also a brassica, so, like cauliflower, it goes pretty well with rhubarb in your garden.
  1. Garlic: Garlic has a scent that keeps most bugs at bay. So, planting it with rhubarb is a great idea. Rhubarb typically suffers from weevil attacks which garlic’s presence would solve.
  1. Broccoli: Broccoli is another brassica, so it’s a great pair for rhubarb. It benefits from rhubarb’s whitefly repelling ability. Also, broccoli doesn’t absorb too many nutrients from the soil to affect rhubarb. 
Rhubarb in Guild

Final Thoughts

Unfortunately, companion planting isn’t a completely solved science yet and still needs a lot of research based on a lot of trial and error that many gardeners are constantly working on. I personally am always trying different companion plants and then observing the benefits or problems.

A book that can really help get you started in the science and practice of companion planting that I really like is “Plant Partners: Science-Based Companion Planting Strategies for the Vegetable Garden” by Jessica Walliser.

Plant Partners: Science-Based Companion Planting Strategies for the Vegetable Garden
  • Walliser, Jessica (Author)
  • English (Publication Language)
  • 216 Pages - 12/22/2020 (Publication Date) - Storey Publishing, LLC (Publisher)

Last update on 2024-06-12 / Affiliate links / Images from Amazon Product Advertising API


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    Author, blogger, podcaster, homesteading and permaculture enthusiast. I have a passion for sharing what I learn and helping others on their journey. If you're looking for me, you'll usually find me in the garden.

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