Is Companion Planting Important?

Does Companion Planting Matter
Companion planting is not as important as you may think.

Companion planting in the garden has been a topic of discussion for many years now. Many people speak about it as though there are combinations of plants that should never be planted together. Is this a true phenomenon or is this an over exaggeration.

I personally have not put much weight into the idea of companion planting. I do realize that there are some plants that do better with others. As someone who has studied plant science in the past I also understand the properties of allelopathic plants. It seems as though the concept of allopathy has been put into overdrive when we start looking at companion planting.

Why Was The Concept Of Companion Planting Developed?

Allelopathic plants affecting a garden setup is not greatly studied. Meaning there is not a lot of data to show that it has actually occurred at the level many claim. With that being said I’ve heard of too many coincidences to completely write off the theory all together.

With more people than ever enjoying gardening and limited space in the city the idea of maximizing space is important. Which is why the concept of companion planting was born. When you start jamming too many plants into a small area you tend to run into some issues. The companion plant concept is an attempt to help people maximize yields in small areas.

In this blog post we will be looking at exactly what companion plants look like. The rules you should consider and follow when deciding on companion planting. Along with companion planting rules that you can loosely follow and ultimately won’t affect the garden.

Does Companion Planting Really Matter? 

The answer kinda sorta. In all honest a majority of companion planting decisions comes down to common sense and knowing your environment. The hype for companion planting is completely born out of fear. The statement about planting certain plants together will cause stunted growth is concerning. Especially if you put many hours of hard work into your garden. 

So let’s look at the science about companion plants. There are two big no-no’s when it comes to planting two plants together. The first big no-no is planting plants together from drastically different environments. The second is planting plants with allelopathic plants. 

Don’t Plant Plants Together From Different Environments

When I’m talking about different environments I am talking about completely different needs. Such as planting a succulent with a pond pond for example. Because these plants have different requirements for water and substrate this would be a poor choice. 

Do Not Plants Heavy Feeders Together

To avoid planting plants together the need drastically different environments look at things such as watering needs, substrate, fertilization and the lighting. A great example of this is not planting heavy feeders together such as tomatoes and corn. The exception to this would be if you are willing to supply the nutrients the plant needs to survive and thrive. If you are wiling to fertilize accordingly feel free to plant these together.

When you look at Allopathic plants we need to consider exactly what makes that plant toxic. Some plants that are considered allelopathic consist of:

  • Asparagus 
  • Beans 
  • Beets 
  • Broccoli 
  • Cabbage 
  • Cucumbers 
  • Peas 
  • Soybeans 
  • Sunflowers 
  • Tomatoes

What Do Allelopathic Plants Do To Surrounding Plants?

What this means is that the plant roots, seeds, or leaves are toxic to potential nearby plants. Despite popular belief this allelopathic property of the plant is not specifically targeting certain types of plants. It is admitting a chemical across the system to prevent plants from sprouting in its vicinity.

This is for self-preservation to ensure that there is very little competition for things such as the lighting and nutrients. In some cases it could be argued the purpose is to prevent overcrowding which will also cause disease and pest issues.

This toxic release is designed to prevent seed germination and there is very little documented evidence that it affects seedlings that have been transplanted. This is were the idea of companion planting tends to get fuzzy. This would mean you can plant whatever you desire together so long as then are germinated and transplanted as seedlings. Without more evidence pointing towards allelopathic properties being strong enough to harm full grown plants I can not say for certain this is possible.  

Fall Is When The Toxins Are Released.

It’s important to note that when these toxins are released into the environment it typically happens around fall. This means if you intend on planting something in your tomato patch from the year before you should ensure that all the leaves and debris is cleaned up. Otherwise you do run the risk of these toxins leaching into the soil and ultimately harming both seedlings and seeds. 

I would argue it’s actually exceedingly rare to see these properties harm seeds or plants during the growing season because it simply is not how these allelopathic plants work. The toxin is sequestered in the leaves and upper biomass, this will not affect a plant until after this biomass has started to decompose. Furthermore the toxic effects are only meant to last for a small period of time before being washed away. This is why composting tomato biomass is still acceptable so long as it is degraded.

Number One Rule Of Companion Plants: Space

If you have a plant listed above that is allelopathic the best rule of thumb is distance. If you are planting another plant that is not in the same family consider using distance. A buffer from the plant will ensure you still receive a harvest from your other crops. These toxins are quickly diluted the farther away from the plant you get.

If spacing is not possible do to a limited amount of area consider placing allelopathic plants into containers. Container gardens in many cases have higher yields when managed correctly.

Do Not Mix Different Heights Without The Sunshine

The second format that companion planting falls into is actually a lot more manageable. We thought that certain brands of height and density should not go together is a simple fix. For example you would not want to plant a tomato with the bush bean. The tomato plant due to its height will shadow the bush bean ultimately resulting in low yields from your bush bean crop.

However this is not always the case. For example if you are in an area that receives a ton of sun. The bush beans are going to be just fine when mixed in with the tomatoes. This is because the sun is able to penetrate the canopy and reach the plants closer to the ground. 

If you plant anything to close together you ultimately run the risk of potentially causing a battle for nutrients and sun. This is why just basic spacing is important regardless of what plants you’re putting together. Something else that is important to consider is pruning the plants to allow for the canopy to properly capture the sun.

In conclusion I believe it’s safe to say that companion planting is more of a fad than a reality. While it’s important to note that allelopathic properties in plants is a very real thing. We don’t want to forget the fact that proper spacing is also important. So long as you have proper spacing in your flowerbeds you are going to be just fine. 

Be sure to print off and be downloadable printable I’ve made it that goes into a bit more detail as to what plants can go together and which ones to avoid.