We Test Our Topsoil, Too. Here’s Why It Matters.
In last week’s post we walked through how we test our mulch. Soil gets the same treatment and in Western Pennsylvania’s clay-heavy landscape, the science behind it matters more than most people realize.
Most people don’t think too hard about where their topsoil comes from. But if you’ve ever had plants fail to thrive, seen water pool after a rain, or dug into your bed and hit something closer to concrete than earth the problem often starts underground. That’s the whole reason we have a testing process.
Every new source starts at Penn State
Anytime we bring in raw material from a new site, samples go to Penn State’s Agricultural Analytical Services Laboratory before a single yard goes into production. PSU Extension is the standard for soil analysis in Pennsylvania the same lab that farmers and homeowners across the Commonwealth have relied on for decades.
Penn State’s Agricultural Analytical Services Lab measures pH, key macronutrients, organic matter, and soil texture. Their reports include lime and fertilizer recommendations based on what the soil actually needs. Reading a PSU soil test report gives a complete picture of what you’re starting with — and that’s exactly what we need before we touch a batch.
Two tests shape every batch we make
Soil pH determines how well plants can access nutrients and how active soil biology is. We test the pH of every new raw material source so we know what we’re working with and whether we need to adjust our blend to reach the neutral starting point your plants need.
This tells us the exact breakdown of sand, silt, and clay. Too much clay and the soil compacts, smothers roots, and blocks drainage. Once we have those numbers, we fine-tune how much O38 organic material we add during screening to hit the right balance.
“Anytime we bring in raw material from a new site, that material is tested at PSU so we know exactly what pH we’re starting with.”
Jayme Matkozich, J.A. Rutter Co.The clay problem that defines Western PA landscaping
If you’ve gardened around Pittsburgh, you already know this. Our soils run heavy. Clay particles pack tightly, leaving little room for air and water movement, blocking root growth, and locking nutrients away from plants. It’s behind most of the drainage problems, compacted beds, and struggling plants our customers come to us about.
We strive to keep our finished screened topsoil at no more than 25–35% clay lower than what you’ll typically dig up in native Western PA soil. The O38 organic material we blend in during screening improves soil structure and creates the airflow and drainage roots actually need to grow.
We test the finished product for the same two things: pH and particle size, approximately every third batch. Because we use the same raw material for at least a full season, this frequency provides meaningful quality checkpoints without redundancy. It’s consistent with Penn State Extension’s own guidance on how often stable soil profiles need testing.
What good topsoil actually looks like
One misconception we hear constantly: people expect screened topsoil to look like the fluffy potting mix from a big-box store. That expectation leads to real confusion and sometimes real frustration.
The misconception
Good topsoil should look like fluffy bagged potting mix.
The reality
Potting mix is engineered for containers. It’s not built for in-ground beds and landscapes.
The misconception
Finer soil is better soil.
The reality
Overly fine soil compacts around roots, cutting off air and water causing slow growth, root rot, or plant death.
The misconception
Chunky topsoil is low quality.
The reality
Larger particles are essential for airflow, drainage, and root expansion in the ground.
We screen our topsoil through a ¾-inch screen by design. That screen size ensures particles are large enough to keep air pockets open and let water move through. The University of Delaware Cooperative Extension documents exactly what happens without badly formed roots, nutrient deficiencies, and drought stress even in well-watered plants.
Pair our screened topsoil with mushroom compost or more O38 for heavy clay beds, and you’re giving your plants a real foundation, not just the appearance of one.
Ready to start with the right foundation?
Our team is happy to help you figure out exactly what your project needs: soil, mulch, or both.
Talk to our team →
