How To Remove Small Rocks From Soil?

When starting a new farm, you may realize that small rocks, gravel, and pebbles impact the properties of your soil in ways that may be unfavorable. In some cases, like when building specialty garden beds or making a soil mix for starting seeds, you may decide to remove small rocks to improve your soil quality. In other cases, like when farming large areas of land, removing them may be unnecessary or too labor-intensive.

Read on to learn more on how to remove small rocks from soil + watch some informative Youtube videos below for a visual guide!

Small Rocks Affect Soil Quality

https://youtu.be/HL8qqsaN8JI

Rocks don’t directly contribute to your soil fertility since they hold little nutrients and are largely void of life.

While they don’t usually cause issues directly, they do take up valuable space that could otherwise be filled with finer biologically active sediments.

Thus if you have a high percentage of rocks in your soil (15% or more) you may choose to remove them to provide more space for better soil.

Impact Of Small Rocks On Soil Quality:

• Reduced water retention
• Reduces nutrient holding capacity
• Can be cumbersome
• Biologically inactive
• Can affect the growth of root crops

Small Rocks Increase Drainage

One of the biggest impacts small rocks can have on your soil is greatly increasing drainage. If you live in a climate with excessive rain this could be beneficial, but if you have a significant dry season then it’s unlikely to serve in your favor.

How Important Is It To Remove Small Rocks?

For most gardening and agricultural projects removing small rocks is not very important and is too labor expensive.

Alternatively, if you want to make high-quality soil for whatever reason then you may want to remove them.

Reasons To Remove Small Rocks:

• Soil for starting seeds
• Soil for bio-intensive beds
• Soil for container gardening
• Planting of certain root crops
• When rock content exceeds 25%
• To reduce drainage in dry climates

Reasons To Leave Small Rocks:

• Working with larger scale agriculture
• To increase drainage in wet climates
• When rock content is less than 15%
• When removing rocks seems too labor intensive

Removing Small Rocks With A Soil Sifter

https://youtu.be/j8-XitNJigk

The best tool to remove small rocks is a Soil Sifter. This tool usually consists of a rectangular or square frame that has a metal mesh with 1/2” or 1/4” holes attached to the bottom.

Sometimes they have handles that allow you to move the sifter with two people.

Using A Soil Sifter With Two People

One of the quickest ways to use a soil sifter is by placing your soil on the mesh and then shaking it back and forth with the help of another person.

Preferably you will sift the soil onto a tarp to avoid mixing it with unsifted soil. Place the small rocks aside and fill again.

Using A Soil Sifter Alone

There are two main ways to use a soil sifter without the help of another person. The first is done by placing your filter on top of a wheelbarrow or container and moving the soil around by hand, allowing the fiber sediments to pass through.

Otherwise, if you have a larger rectangular sifter you can place it at a 40-degree angle and throw shovel-fulls of soil at the soil sifter. Finer sediments will pass through to the bottom while small rocks will gently roll down the sifter.

Other Alternatives

In some cases you may be able to separate a large quantity of rocks just using a rake. Circular “washing machine” like soil sitters known as Soil Tremblers are another good option if you plan to sift a lot of soil.

What To Do With Small Rocks

After having separated small rocks from your soil you may be wondering what you can do with them. Thankfully they can be a great material.

Common Uses For Small Rocks:

• Soil for a succulent or dry garden
• To improve drainage
• Slow water in drainage ways
• As filler material
• Can act as a natural mulch
• As a construction material
• As decoration in the garden
• As a thermal mass

Improving Soil With Excessive Amounts of Small Rocks

First, you’ll want to remove as many of the rocks as you have the motivation to do so. Any soils with more than 20% small rocks will be difficult to cultivate so aim below this number.

You will then want to amend your soil with compost, biochar, and other natural soil amendments.

Mix these into your soil and then lay a thick layer of plant-based mulch on your soil surface. With this and other regenerative agricultural practices, you can mitigate any negative impacts that small rocks may have on your soil.

Frequently Asked Questions

If you have rock mulch in your garden, why would you want to get rid of it?

If you’ve moved into a house that has old landscape gravel in place, or if you put it in place yourself , there are a number of reasons why you might want to remove it. If it’s been in place for a while, it may be looking shabby. The soil beneath it may be compacted. If you want to change the planting (e.g. from cacti to flowering plants) you’ll need to remove the gravel mulch and till and amend the soil to ensure success with your new planting.

What tools do you need to have on hand to get rid of unwanted rock mulch?

To make quick work of your rock mulch removal project, assemble these tools in advance:

• Rock-sifting shovel or dirt sifter
• Shovel with a pointed blade
• Rock-screening or bow rake
• Wheelbarrow

What can you do to get rid of the top layer of rock mulch on garden soil?

You can use your rock-screening or bow rake to rake up the rocks and gather them into convenient piles. The sturdy, narrow tines of these tools make them perfect for gathering up rocks while allowing soil to sift through and stay in place.

Can you just use a regular garden rake or a lawn rake to remove surface rock mulch?

It’s possible to use a plain garden rake for this job, but the tines are so short and far apart that you’ll find yourself doing a lot more work than you would with the right tools. A leaf rake has long enough tines spaced close together, but the tines are probably not sturdy enough to deal with rocks.

Why not just shovel the rock mulch up to begin with?

Shoveling can be backbreaking work. It’s better to gather all the rocks into piles and then shovel them into the wheelbarrow. Trying to shovel them straight from the ground into the wheelbarrow would take a lot longer, and it would be very tiring!

What do you do if you find landscape fiber under the rock mulch?

Rejoice! This will make your job a lot easier. Just find the edge of the cloth and lift it bit-by-bit to form “sacks” that allow you to pick the rocks up in bundles and place them in your wheelbarrow with little or no raking or shoveling.

How can you remove rock mulch that has settled or been tilled into the soil?

Take your pointy shovel and dig up the soil. Place it into a soil sieve or sifter. Shake the sifter over the area you have just dug up. This will allow the soil to go back into place, and you can remove the rocks. Another option is to use a rock-sifting shovel. This will save you a step.

What if there are lots of rocks and gravel mixed into your soil?

To deal with rocky soil, you’ll need a more extensive list of equipment. Have these things on hand:

• Rock-sifting shovel or dirt sifter
• Landscape or bow rake
• Hand trowel shovel
• Pointed shovel
• Digging fork
• Wheelbarrow
• Rototiller

Begin by breaking up the soil with the Rototiller. Work carefully, and remove large rocks (e.g. baseball sized) by hand as you till. Follow up by raking away surface rocks and then go to work with your digging fork, rock sifting shovel or combination of pointy shovel and dirt sifter. Your goal is to locate and remove rocks to a depth of about 17 inches.