Structural Soil That Supports
Roots and Roads

ERTH's structural soil for trees lets urban trees thrive beneath paved surfaces, without sacrificing the load-bearing integrity your project requires. Specified by engineers across Georgia.

About Structural Soil

Urban development has always asked trees and pavement to share the same space. For most of paving's history, the pavement won. Trees planted in standard compacted base material—the same material that keeps sidewalks and parking lots stable, are effectively cut off from the soil conditions they need to grow. Roots push upward toward oxygen and moisture, eventually buckling the pavement above them. The trees decline. The pavement gets replaced. And the cycle repeats.

How Structural Soil Breaks the Cycle

Structural soil was developed to break that cycle, and ERTH Products has been supplying structural soil solutions to landscape architects, civil engineers, and grading contractors across Georgia for years. We offer two proven products: ERTH-HydRocks Structural Soil, our proprietary structural soil mix engineered for high-load urban applications, and CU Structural Soil Mix, based on the Cornell University specification that has become a widely adopted standard in the landscape architecture industry for urban tree pit installations. Both products work on the same principle: engineered void space within a load-bearing matrix. The aggregate structure of the mix carries the compaction loads required for paved surfaces, meeting Georgia DOT and municipal infrastructure standards—while the void space within that structure preserves room for root growth, oxygen exchange, and water movement. Trees planted in structural soil for trees develop healthy root systems that grow downward and outward through the soil column rather than toward the surface, extending tree longevity and dramatically reducing the pavement heave that costs municipalities millions in maintenance costs annually.

Two Proven Products, One Reliable Source

Both ERTH-HydRocks Structural Soil and CU Structural Soil Mix are built on an ERTH Food Compost organic base in Plains, Georgia, which provides the microbial life and nutrient foundation that supports tree health over the long term, not just root accommodation. Our hydrocks structural soil and CU spec products are available with full technical documentation for project submittals. Spec sheets, cu structural soil specification documentation, and load-bearing performance data are available on request. Our team in Tyrone, GA works directly with landscape architects and civil engineers from spec development through project delivery, supplying structural soil in bulk throughout Georgia and the Southeast.

Structural Soil Available Across Georgia

Find ERTH structural soil products through our contractor and distributor network across Georgia.

What Our Customers Are Saying

From bioretention to structural support, our engineered mixes are tailored for performance and compliance.

At Heritage Landscape Services, Inc. – Gilbert, SC
Hagins Landscape Nursery, Inc. – Greenville, SC
“I have used ERTH Food® for six years as a soil amendment and as a mulch in annual color beds. With regular use, I have seen an overall improvement in the quality of the soil. Specifically, I have seen better water retention and a reduction in the occurrence of disease.

“ERTH Food® is a great substitute for mulch. It has a good color and texture and does not wash or blow away as do some other mulch products. Far less disease appears in our flowerbeds, which reduces our chemical use and produces more vibrant colors. ERTH Food® is a great product."

Owen Mattis

Liam Donovan

"At Heritage Landscape Services, Inc. – Gilbert, SC At Heritage Landscape, Inc., we have been using ERTH Food® for many years and are very pleased with it. It is a product that we can continue to use throughout the growing season to refresh the look of our beds without changing the beds’ appearance. It has a unique consistency in color and texture that continues the flow into other areas of the bed. ERTH Food® makes a perfect blend to the property, while it gives a fresh look without causing too much contrast. It never fails that, while we are planting our beds, a passer-by will stop to ask what we are mulching our beds with. They comment on how good it looks and ask for the name of a local place where they too can purchase ERTH Food®.
“We find, however, that ERTH Food® provides more than just aesthetics to our beds. It gives our beds a good barrier against weeds, and we’ve found that it also creates a moisture barrier that allows moisture to stay in the ground longer than any other mulch we have tried. At the end of a growing season, we will pull the old flowers and till the existing ERTH Food® into the soil; this provides an excellent source of organic matter that most of our beds need because of either the high clay or sand composite. The bags are an easy-to-handle size, which makes transportation to the beds easy. ERTH Food® is a great product for anyone wanting to achieve that extra-professional look for their beds, and it is ideal for flower bed enhancement."

John Bettis

Heritage Landscape, Inc.

"Riverbanks Zoo & Botanical Garden – Columbia, SC
“At Riverbanks Zoo and Botanical Garden, we have been using ERTH Food® for a number of years. While many people use it as a soil conditioner, we use it as a mulch for our beds. We must get hundreds of questions about ERTH Food® every year; people are intrigued about the peanut shells.
“One thing that is important to me when purchasing mulch is to ensure that it is weed-free. We’ve never had a problem with weedy ERTH Food®. ERTH Food® is a unique and useful product, and, most of all, it looks great as a mulch.”"

Andy Cabe

Riverbanks Zoo and Botanical Garden
Get in touch
Form

FAQs

All You Need to Know

01
What is structural soil and where is it most commonly used in construction and landscaping?

Structural soil is an engineered blend of aggregate and organic material that supports compaction loads from paved surfaces while preserving pore space for tree root growth. Most commonly used in urban tree pits beneath sidewalks, parking lots, plazas, and streetscapes, anywhere trees and pavement must coexist.

02
How does structural soil support tree root growth underneath paved surfaces like sidewalks and parking lots?

Standard compacted base leaves no viable pore space for roots, forcing them toward the surface where they buckle pavement. Structural soil maintains engineered void space within a load-bearing matrix, allowing roots to grow down and outward, extending tree life and reducing infrastructure maintenance costs.

03
What load-bearing specifications does ERTH Products' structural soil meet for urban infrastructure projects?

ERTH's structural soil products are engineered to meet the compaction and load-bearing standards for Georgia DOT and municipal streetscape projects. Contact our team or request a spec sheet for your project requirements.

04
What is the difference between ERTH-HydRocks Structural Soil and CU-Structural Soil Mix?

ERTH-HydRocks Structural Soil is ERTH Products' proprietary blend engineered for high-load urban applications. CU Structural Soil Mix is based on the Cornell University specification—a widely adopted landscape architecture standard for urban tree pit installations. Both are available through ERTH Products in Georgia. Our team can help determine which fits your spec.

05
Can structural soil be used in Georgia DOT road and streetscape projects?

Yes. ERTH Products' structural soil products have been used on Georgia DOT and municipal streetscape projects, engineered to meet the load-bearing requirements these applications demand. Spec documentation available on request.

06
Does ERTH's structural soil help with stormwater infiltration and reducing urban runoff?

Yes. The engineered void space in our structural soil mix supports stormwater infiltration beneath paved surfaces, contributing to runoff reduction in urban environments. For projects with primary stormwater infiltration requirements, our bio retention soil may be the more appropriate product, though structural soil contributes meaningfully to overall stormwater performance.