17 Benefits Of Compost

Composting is one of the single best thing every homeowner can do to better their yard, garden, soil, and help the planet by reducing landfill space and lowering their carbon footprint. Every backyard should contain a compost pile or bin, as they don’t take up much space and provide a free source of fertilizer that is regenerative. And, if the pile is built correctly and balanced, it will not attract animals or smell.

I probably make a cubic yard of compost each year, starting and finishing 8-12 piles (depending on material I can get). I built my first pile in 2016 and never looked back, and usually have 2-3 piles at various stages of decomposition. And throughout these years I’ve grown to appreciate all the benefits my vegetable garden, flower beds, and even my lawn receive from compost. The bottom line is that compost is the single best amendment for soil. And now I will show you all of it’s benefits in one place.

***Also – if after reading this you are interested in learning how to make your own compost, see our detailed guide for the basics, and an additional version for composting in winter.

1 – Compost adds fertility and nutrients to soil

Finished compost contains nutrients and minerals that are readily available for plant roots to absorb^[1]. This will help plants stay healthier and grow larger, ultimately improving yields. The best part is that since compost is in the form of decomposed organic matter, it will be slow release, giving up it’s nutrients as plant roots need them. Unlike synthetic fertilizers that can be washed away quickly.

2 – Improves our garden yields

The flowers and vegetables we grow need nutrients and minerals. And the fact that we can add these for free by topdressing our gardens with compost mean we will get increased yields. Whether it is from more and larger flowers to larger and more veggies – it all will happen by adding compost.

3 – Improve soil structure

This is quite possibly the most important benefit, or at least tied with the improved fertility. Compost, added to soil will improve the soil structure, as it is just the final form of decomposed organic matter.

When organic matter is added to the soil it gets transferred to the lower depths naturally via worms and via pores in the soil. This organic matter will eventually form into a glue like substance helping soil bond into large clods of particles, which provides soil structure. But these large clods of particles also have voids between them, which also creates voids and pathways for roots, worms, water, and more organic matter^[2]. Thys the symbiotic relationships with soil organisms can flourish with this improved structure and added organic matter.

4 – Improves soil drainage

About that improved soil structure……the natural voids formed via improved structure will improve the drainage in heavy soil textures, such as clay^[2]. Compacted soils and clays often are referred to as ‘structureless’ in that there are no natural voids in them, and thus they don’t drain water very well. If you notice water pooling on a lawn, it may very well be that the soil is either over compacted or heavy clay.

But the drainage improvement doesn’t stop for heavy soils. Adding compost to sandy soils will actually slow down the water drainage rate. The organic matter helps provide structureless soils with structure, holding sandy particles closer together to better capture water and reduce the drainage rate.

5 – Aerate the roots / reduce compaction naturally

The improvement in soil structure will naturally transfer oxygen to the soil in the form of voids/pathways. This aeration will help improve the microbes in the soil by allowing other organic matter to decompose via aerobic bacteria, as opposed to anaerobic bacteria.

6 – Plant roots can go deeper

Because of the reduced soil compaction plant roots will be able to develop more thoroughly and grow deeper. For instance in un-compacted soil did you know tomato roots can grow over 4′ (1.3m) deep in a single growing season? But in compacted soil (like that which used to be turf grass/lawn) they have trouble growing much deeper than their original planting depth.

Deeper plant roots mean more access to nutrients and minerals, and the ability to access water that is deeper in the ground. This will in-turn mean you don’t have to water as much as well as having larger, more vigorous plants.

Related – See my 5-year garden soil transformation using leaf mulch

7 – Improves water infiltration

The natural pathways that soil structure creates? Well, that means more water can enter the soil! Soils that are over-compacted, or heavy soils such as clay (structureless) often have a hard time absorbing water. There just isn’t anywhere for the water to go, which leads to the water eventually being lost to evaporation.

Well, the pores opened up by worms and by soil structure forming allow for that water to penetrate deeper into the ground. This can allow the water table to store more water, being available for roots.

8 – Improves moisture retention / conserve water

The improved infiltration and drainage mentioned above both serve to directly conserve water. Better water infiltration, plus faster draining for clay soils, and slower draining for sandy soils all equal less water lost to evaporation or excess drainage. Adding compost to soils that are nearly full sand or full clay is just about the best way to improve how they interact with water..

*Note – if you’re unsure what kind of soil texture you have, you can find how to do a quick and dirty test here, and a more precise test here. Don’t worry, you won’t need any special equipment for either test.

9 – Prevents fungus by aerating roots

All of the improved soil structure and reduced compaction mean more oxygen at our plant roots. And this means the roots are less likely to be ‘drowning’ from poor draining soil. Fungus thrives in overly wet, low-oxygen environments, and this added aeration will naturally fight off fungi before they begin by denying them their environment.

10 – Improve disease resistance of plants

The addition of compost helps us to have healthy soil full of nutrients. This will in-turn create very healthy, vigorous plants. And this in-turn will help keep them equipped to stop any disease before it can take hold. The addition of organic matter will also feed soil organisms that help control pathogen populations ^[3].

You see, plants generally are able to fight off many disease and fungi naturally as long as they are healthy. It is sickly plants that are the most susceptible to pathogens. Keeping our plants healthy via the availability of compost therefore helps prevent disease.

11 – Saves money (no $$ on fertilizer)

And this almost goes without saying, but if you use compost as your primary soil amendment, you shouldn’t need to purchase supplemental fertilizer. Now, if you are just starting your vegetable garden from scratch, it may take a few years to build up your soil (by using compost and leaf mulches), but in the end you should be able to grow large vegetable plants with high yields without the extra money spent on fertilizers.

I believe the last growing season in which I used a fertilizer on my vegetable garden was 2019…..Since then I have built up my soil with compost (amending when transplanting, topdressing in Fall) and thick leaf mulch. The results has been nothing short of extraordinary.

12 – Composting saves landfill space

Composting is the most efficient form of recycling for a homeowner. Food and yard waste broken down naturally in your backyard and then used in the garden or yard does not go into your trash, and thus reduces landfill space. Considering the average household generates 650 lbs of waste each year, the landfill space can really add up^[4]!

13 – Composting reduces your carbon footprint

Since you are not throwing away kitchen scraps or yard waste, that means that the trash trucks don’t need to haul it away. And reducing weight will directly improve the fuel economy of the garbage trucks. Furthermore it is less material for landfill equipment to move, saving even more fuel.

14 – Reduce methane and capture carbon

As food rots in a landfill, it is composting anaerobically. This type of compost is also known as ‘cold composting’, and it generates methane, which is a greenhouse gas that is ten times as potent as CO2^[5]. By hot composting our food scraps we are doing so aerobically, which results in significantly less methane production^[6][7].

15 – Exercise

The process of composting, whether gathering or prepping materials or just turning your pile can be quite the workout. Not only does it build muscles all throughout your body, it gives you a cardiovascular workout too. I am often sweating after thoroughly turning a pile. Composting isn’t just another way to keep fit, but you get some of the best free soil amendment available!

16 – Keep synthetic chemicals away from our yards and garden

Using natural organic compost that you make yourself in-place of store bought fertilizers or chemicals is beneficial in that you know what is in it, it’s free, and there is no added risk as long as you used organic materials.

People who want to have natural or organic gardens generally have two options for feralization. First, they can make their own compost, controlling the ingredients from start to finish. Second, they can purchase compost or organic fertilizers made by companies or 3rd parties. However, once in a while purchased materials may be contaminated with pesticides or other chemicals, even if it is advertised as not.

Take this example when a company who made compost from residential yard trimmings inadvertently had it contaminated with a herbicide^[8]. What happened was many people had their lawns treated commercially with herbicide that lasted for a very long time (Clopyralid). But, they had to dispose of their lawn clippings separately to reduce landfill space, and were inadvertently composted. The lawncare company who treated their lawns knew that this herbicide was not supposed to be composted, but the homeowners did not. The finished compost was contaminated with the herbicide.

17 – Reduce pathogens in soil

Look, the overall improvement of soil structure, water infiltration, reduced compaction, and addition of organic matter means that you will have a healthy soil food-web. The organic matter added by compost will cause an explosion in the population of soil microorganisms, which help control plant pathogens^[3]. Keeping this balanced by feeding it with compost and organic matter means that various micro-organisms will keep a healthy environment for roots so that your plants can thrive.

Conclusion

I’ve just listed out 17 different ways that compost can help your garden. Adding compost will improve your soil structure, fertility, disease resistance as well as be helpful for the environment and save you money at the same time! So what are you waiting for? Here are several guides I’ve written that will help get you started:

• How to start a compost pile
• A (printable) list of 101 household items you can compost
• Tips on composting year round (even in winter) and alternative materials

Find more gardening tips here