Do You Add Compost Before Or After Tilling?

When it comes to preparing the soil for planting in your garden, there’s a big question: Should you add compost to the soil before tilling or after? 

While adding compost before tilling is the most popular method, there are some benefits to adding it afterward as well. Applying it beforehand allows you to mix it in thoroughly with the tiller, whereas spreading it on once you’ve finished may be more cost-effective.

In this article, we’ll explore the benefits of compost and the importance of its use during a session with your rototiller. We’ll also dive into the arguments for adding compost before or after tilling so that you can decide which is the best option for your yard.

Why Should You Use Compost When Tilling?

Compost is like a magic potion for plants. It’s made from things like food scraps, leaves, and grass clippings that break down into a rich, dark, organic nutrient-rich material. The best way to dig this into the soil is to add the compost at some point during the tilling process. 

The Benefits Of Using Compost

Using compost in your soil has many benefits. First, it improves the soil’s texture and structure. It makes the soil nice and crumbly, which helps plants grow better (I talked about this before in my article about prepping soil for rototilling). 

Compost also aids the soil in holding onto water, so plants don’t get thirsty as quickly. Plus, it’s full of important nutrients that plants need, like nitrogen, phosphorus, and potassium. 

Adding Compost While Tilling

When we till our garden, we’re cultivating the soil to get it ready for planting. 

Adding compost into the mix when tilling is a great idea as it’s the most efficient method to get the compost into the soil.

Many gardeners like to cover the ground with compost before they go over it with a rotary tiller whereas others prefer to spread it on after tilling. Let’s explore the benefits of both methods.

Why Add Compost Before Tilling?

There’s no doubt that the most popular method for adding compost to your garden is to spread it on the ground before you start tilling.

There are several reasons for this as follows:

The Easiest Way To Mix Compost In

Many gardening experts believe that you get the most benefits from compost by thoroughly mixing it into the soil to a good depth. If you’re tilling your garden with a rotary tiller this is a great opportunity to do this without having to dig it in by hand. 

Improving The Soil Structure And Texture

Both compost and tilling are amazing for improving the soil’s structure and texture. Combining the two is a great way to ensure that the compost is worked into the soil to a sufficient depth to get the most benefit.

Preventing Nutrient Runoff And Soil Erosion

One problem with repeated tilling of the ground is that it can cause nutrients and beneficial organisms to rise to the surface and get washed away with rainwater or destroyed by the sun. 

As the topsoil usually ends up very fine after you’ve finished working the ground with your rototiller, this can also lead to soil erosion as it gets washed away by storms or blown away by strong winds.

By adding compost to the soil before you start work the effects of this can be minimized. 

Nutrients are added back into the soil straight away while the binding properties of a good compost hold the topsoil together so that it’s still easy to work with but doesn’t get blown away.

Why You Should Add Compost After Tilling

While adding compost before tilling has its advantages, there are also a couple of reasons why adding compost after tilling may be preferred. Let’s explore some of the benefits of this approach:

Minimization Of Nutrient Loss 

As we know, tilling the soil can result in the loss of nutrients through exposure to air and the mixing action. By adding compost after tilling, you can minimize this nutrient loss. 

The compost gets added directly into the topsoil, replenishing any nutrients that may have been disturbed during tilling. This ensures that plants have a rich source of nutrients available to them right from the start.

Compost mixture
Compost mixture

More Cost Effective

Adding compost after you’ve tilled the ground allows you to reduce the amount you need to use making it the cheaper alternative.

This is because you can adjust the amount and type of compost you need to apply based on the specific needs of different areas in your garden after working on it with your rototiller.

How To Add Compost Before And After Tilling

Whether you decide to add your compost beforehand or afterward, it helps to know the best ways to apply it.

Guidelines For Adding Compost Before Tilling

Use mature compost: Ensure that the compost you add before tilling is well-aged and fully decomposed. This helps minimize nutrient loss during the tilling process and provides a stable source of nutrients for plants.

Spread compost evenly: Distribute the compost uniformly across the garden area before cultivating. This ensures that nutrients are distributed evenly throughout the soil and promotes consistent plant growth.

Avoid over-tilling: Excessive tilling can disrupt the soil structure and lead to nutrient loss. Tilling to a depth of 6-8 inches is usually sufficient for incorporating compost while maintaining soil integrity. If you aren’t sure how you can adjust your tiller, check out this article I wrote a while ago. 

Guidelines For Adding Compost After Tilling

Choose quality compost: Similar to adding compost before tilling, opt for mature and well-decomposed compost. This ensures that the nutrients are readily available to the plants.

Spread and incorporate compost thoroughly: After tilling, spread a layer of compost evenly across the soil surface. Use a garden rake or hoe to incorporate the compost into the top few inches of soil. This allows for better nutrient distribution and mixing.

Adjust compost quantity: Assess the soil condition after tilling and determine the appropriate amount of compost to add. Adjust the compost application accordingly to optimize plant growth.

Case-By-Case Scenarios And Suggestions

Every garden is unique, and different situations may call for specific approaches. For example:

  • If your soil is already rich in nutrients, adding compost after tilling may be sufficient.
  • If your soil lacks organic matter, adding compost before tilling is the best way to add nutrients and structure deep into the ground.

In each case, consider the specific needs of your garden, soil condition, and the plants you are growing for the best results. 


In most cases, adding compost before tilling is the preferred option for many gardeners.

However, experimentation and observation will guide you toward the best approach for adding compost before or after tilling in your specific gardening situation.

Peter Toth

Hi! I'm Peter, the owner of BackyardGadget. Working around the house has always been a big part of my life. I've created this site to share my experience, and to help people choose the right tools for the job. Thank you for stopping by!

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