Soil Profile

Posted on Category:Edible Plant Growing Information

Have you dug up your yard recently? If you live in a newly built home, you may be surprised at what you find in your soil profile below the sod.

Marquis Soil profile photo
Photo of a Marquis series soil profile in Goodhue County, MN

Contents

Background

Don’t make the mistake my family and I made when we first moved into our new home in 2011. We purchased a new home in Dundas, MN and our first mission was to grow a garden.

It failed! 

Where’s the topsoil?

Why did it fail? I didn’t know it at the time, but there wasn’t any topsoil left. The builder removed all of the topsoil and dropped sod on the subsoil!  You see the tan colored soil in the photo above? That’s the subsoil layer which lives below the topsoil. It contains mostly silt and clay with very few mineral nutrients for plants. The actual nutrition for plants (and grass!) is contained in the topsoil and was missing from our yard. You’ll know if you have topsoil or not by digging down into the earth. Healthy topsoil should have a dark chocolate color to it like the photo above. Check out the UC-Davis website called SoilWeb for more information on your property. You can type in your street address and look to see what you’re “supposed” to have under your feet.

What does it mean?

If your topsoil is AWOL, it means anything you try to grow on your property will suffer. Vegetable gardens won’t survive and thrive. Even fruit trees and fruiting bushes or vines will struggle to find the minerals they need to grow correctly. If you’d like to have a lush green sod, that will also suffer. Weeds will like it though. I’m pretty confident that news doesn’t excite you though.

Here’s some more news:

Here are some of the reasons why it’s such a BIG deal for your yard to be missing topsoil in the soil profile:

  • Topsoil is composed of minerals and nutrients recycled from organic material (materials like cut grass, leaves, dog manure, etc). It took much longer than our lifetimes to create that topsoil. It means we’re not going to see the topsoil recreated in our lifetimes. I try not to dwell on this point. Otherwise, I get depressed. No time for depression!
  • Topsoil serves as a gigantic sponge. When we have a rain event, the water penetrates the topsoil and is held in the pores of the topsoil along with the subsoil to a certain extent. When the topsoil is missing, there’s no sponge to soak up and hold the water. This results in water running off the surface. We saw this a lot at our last house. The water would pool up on the sod and then run off the property into the watershed (sanitary sewer drain). There’s also the problem of too much water sitting on the soil surface. In other words, you get the “sloshing” sound when you walk over the sod.
  • Topsoil contains life!!! All of the beneficial organisms like earthworms, beneficial bacteria, fungi, etc. live in the topsoil. When the topsoil is removed, their home is removed also. Ever had problems with insects attacking your new home? It’s probably due to their environment being disturbed.

Weeds anyone?

  • Not having sufficient topsoil creates a perfect environment for pioneer weeds to flourish. If you look at degraded soil, what will you likely see? WEEDS! Weeds do have a job, and their job is to hold the soil. Some of the first plants to populate an area like this are weeds. After cycles of weeds have come and gone, new organic matter is added to the soil. This allows other plants to populate and spread…eventually…many years in the future.

What are my options?

There are really only two practical options. If I had a magic wand in my possession, I’d of course put the topsoil back where it belongs—in the soil profile! Alas, my wand broke last week, so we’re left with basically two choices:

  1. Do nothing and fight the subsoil. This will result in pain and suffering for any plant trying to survive. This will also result in your pain and suffering as you watch in horror as I did. I killed many plants due to this core issue. I’m not ashamed to admit that fact. It was a hard lesson to learn.   
  2. Go vertical. Building vertical with raised beds and/or containers is the best option. It basically replaces the topsoil which was removed in the first place. This allows you to recreate the best growing environment for your plants. However, it’s a lot of work. I manually moved over 16 cubic yards of compost and topsoil by hand and wheelbarrow to fill 18 – 4’x8’ grow beds over the course of three growing seasons. Phew!!! It’s making me tired thinking about that again.

A quick backstory on the creation of MEG

For those of you that haven’t heard the reason for MEG’s creation, here it is: MEG was created to solve the problem of missing topsoil and growing food in urban/suburban locations. BOOM! Now you know the backstory to MEG’s Edible Landscapes.

Spurred on by the pandemic and the run on seeds, I tried to come up with a way of solving this core soil profile problem in the easiest and most direct way. Grow bags were the solution. It’s a method of growing plants without a lot of fuss and is an relatively inexpensive way of accomplishing growing food without having to truck in cubic yards of compost and topsoil to add to the soil profile.

Final Notes:

Yeah, missing topsoil that should have come with your new home is kind of a bummer. However, it’s not all doom and gloom. Going vertical is a great way of working around this issue. If you’re planning on staying in the home for awhile, raised grow beds are a good investment. Otherwise, you can’t go wrong with containers!