What are Incompatible Garden Plants? (Helpful Examples)

Mix vegetable in a basket

Most gardeners don’t have the time or knowledge to know which types of vegetables or plants should grow together. Planting them affects their growth and eventually turns out into less crop yield.

In this blog, we will give you examples and information about Incompatible Garden Plants and why we should avoid them planting together.

Incompatible Garden Plants: What are they?

As I discussed earlier in our previous blog, some plants can grow well together, but some seem to hate each other.

They are called Incompatible Garden Plants, a group of plants that cannot plant together because they cause an effect when they grow in the same soil.

There are several reasons why they can’t go well. Some plants produce chemicals that can affect the growth of other plants; they are known as Allelopathic Plants, while other plants are vulnerable to pests and parasites that can be harmful to others.

If you are still confused about the idea, it is just the same as you start planting tall plants beside the short plants, and eventually, tall plants will limit the water and sun that needs by the shorter plants.

There’s a competition of basic needs between the two. Thus they are incompatible with each other.

With this, companion planting is a must to get good quality results and higher crop yields in your garden.

Let’s find out what plants are not compatible with each other.

Examples of Plants That are NOT Compatible with Other Plants

The following examples below are only the primary plants we found based on the trusted articles we collected, and we fuse them into a table format for easy access. 

You will see in the table why they do not plant together and what other plants should NOT mix with them.

Plants Not Compatible With Reasons Other Plants Should Not Be Planted
1. Eggplant Fennel Fennel produces chemicals that can slow the growth of the eggplant. Nightshade families will compete for nutrients and be more susceptible to blight. Tomatoes, Peppers, Potatoes, and any plants in Nightshade Family.
2. Carrots Dill They attract pests. Parsnips and Fennel
3. Peppers Fennel, Kohlrabi Fennel tends to be antagonistic. Apricot Trees, Beans, Broccoli, Cabbage
4. Pumpkins Potatoes Susceptible to Blight. Spinach, Cucumber, Tomatoes, Potatoes, Squash, Sunflower
5. Cucumber Basil Herbs have intense flavors that harm the taste of cucumber. Herbs like sage, rosemary, and marjoram
6.  Asparagus Any other fruits or vegetables The vegetable can easily stunt the Asparagus if they are too close. Garlic, Onions, Potatoes
7. Lettuce Onion Lettuce competes for the same nutrient as Allium Family needs. Garlic and onions produce chemicals that inhibit the growth of Lettuce. Garlic, Shallot, or any plants in Allium Family
8. Onions Garlic Both of them can stunt the growth of each other and are prone to the same pests and diseases. Lettuce, Leeks, and Shallots
9. Radishes Broccoli Radishes don’t play nice with the plants mentioned. Cabbage, Cauliflower, Kohlrabi, Potatoes, Turnips, Grapes
10. Corn Tomatoes The stalk of the corn can easily stunt the growth of tomatoes, and they are both susceptible to similar fungal infections.  
11. Melons Squash Both plants can create a problematic garden bed to manage, and they are prone to many of the same pests and diseases.  
12. Garlic Beans They won’t thrive and may develop off-flavors Peas, Peas, and other legumes
13. Spinach Potatoes The shallow roots of spinach will compete with the surface roots of the potatoes.  
14. Strawberry Cabbage The cabbage plant attracts pests and can inhibit the growth of the strawberry. Broccoli, Kale, and Cauliflower
15. Cauliflower Cabbage Both are more likely afflict by club roots, a fungal disease that can cause the roots to swell.  

Companion Planting: What is it?

The only way to avoid incompatible plants in your garden is to do Companion Planting

Companion Planting is the best practice conducted by farmers and gardeners today to avoid low-quality crops and fruits, low crop yield, prevent pests and disease from the plants, or even prevent competition for the necessary nutrients.

Though plants are suitable to be accompanied by others, which can attract pollinators or any benefits might consider, beginner gardeners need to know the essence of companion planting that can help them make their garden healthy and bounty.

So how does Companion Planting work?

The idea is easy to understand. 

The other plant can plant the specific plant, and both of them can receive benefits for their growth and development.

We will make another blog post soon regarding Companion Planting and examples of plants that can accompany each other.


In gardening, preventive awareness is always necessary when it comes to planting vegetables and crops. 

Understanding the effect of planting incompatible plants, you can avoid planting many different plants in the soil, so it will not harm your garden.

But remember, if you do not know the effect of some plant, do not risk it and do not plant it. Always do companion planting for a better result and avoid failure.