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Heavy Weight Topsoil 70/30 Mix (Soil / Compost Blend)


Heavy Weight Topsoil 70/30 Mix is a nutrient-rich soil blend made from approximately 70% screened topsoil and 30% green waste compost, designed for projects that require a dense, stable, and fertile growing base. This mix is heavier and more mineral-based than lighter garden mixes, making it ideal for grading, building up planting areas, mounds and establishing long-lasting soil structure while still providing essential organic matter for plant health.

It delivers the perfect balance between:

Structure (topsoil) for stability and compaction resistance

Nutrients (compost) for plant growth and soil biology


Common Uses

  • Soil for building mounds

  • Rough grading with improved soil quality

  • Building up general planting areas

  • Backfilling planter boxes and landscape zones

  • Soil improvement for poor native soils

  • New construction landscape prep


Why Choose a 70/30 Heavy Mix?

Unlike lighter mixes (like 50/50), this 70/30 blend holds its shape better, making it ideal when you need soil that:

  • Doesn’t settle excessively after installation

  • Provides better support for turf and landscaping

  • Handles foot traffic and light equipment

  • Maintains grade over time

It’s especially useful for contractors and large-scale landscape projects where consistency and durability matter.


Material Specifications

Composition

  • Blend Ratio: ~70% Screened Topsoil / ~30% Green Waste Compost

  • Topsoil Component: Native mineral soil with sand, silt, and clay

  • Compost Component: Recycled organic material (green waste, decomposed plant matter)


Material Characteristics

  • Color: Dark brown to earthy gray (varies by source and moisture)

  • Texture: Medium-heavy soil with visible organic matter (small wood fragments may be present)

  • Consistency: Dense, workable, and slightly clumpy when moist

  • Screening: Typically screened, but may contain small debris such as wood chips or fine roots


Performance Properties

  • Drainage: Moderate drainage (better than native soil, slower than sandy mixes)

  • Compaction: Good compaction for grading and base applications

  • Nutrient Content: Moderate to high (from compost content)

  • Water Retention: High — helps retain moisture for plant roots


What Makes it "Heavy Weight"

This mix contains a higher percentage of mineral soil, giving it:

  • Greater density and load-bearing ability

  • Reduced settling compared to lighter mixes

  • Better performance for grade building and structural landscaping


Important Notes:

  • Natural product — color, texture, and composition may vary

  • May contain small rocks, wood fragments, or organic debris (normal for bulk soil blends)

  • Moisture content can affect appearance and weight at time of delivery

  • Not a precision-engineered soil (not for spec projects, request engineered soil blends)


Coverage Guide & Ordering Information

Coverage Per Cubic Yard

Use this as a quick reference when planning your project:

1 cubic yard covers:

~150 sq ft at 2” depth

~100 sq ft at 3” depth

~75 sq ft at 4” depth


How Much Heavy Weight Topsoil do you need?

Basic formula:

Length (ft) × Width (ft) × Depth (ft) ÷ 27 = Cubic Yards

Example:

20 ft × 30 ft area at 3” depth (0.25 ft)

= ~5.5 cubic yards


Truck Load Size average

Small Dump Truck:

~7–8 cubic yards of soil blends

Best for tight access, driveways, residential deliveries

Large Dump Truck:

~35–40 cubic yards of soil blends

Ideal for large projects, contractors, and bulk orders


Delivery Notes

  • One material per load (no mixing different products)

  • Dump location must be flat, accessible, and clear of obstacles

  • Soil is delivered loose — expect a pile, not spread service

  • Moisture content can affect volume appearance at delivery

  • Free Delivery is offered on 10+ yards to select areas only.

We deliver Heavyweight Topsoil 70/30 soil blend mix through out Contra Costa county, Solano county, Alameda, and Marin county cities.


Pro Tip (contractor insight)

Order slightly more than calculated (7–10% extra) to account for:

  • Compaction

  • Minor grading adjustments

  • Waste or uneven ground



Frequently Asked Questions — Heavy Weight Topsoil 70/30 Mix

What is a 70/30 topsoil mix?

A 70/30 mix is a blend of approximately 70% screened topsoil and 30% green waste compost. It provides a balance of soil structure and nutrients, making it ideal for grading, lawn prep, and general landscaping.


How is this different from a 50/50 mix?

A 70/30 mix is heavier and more stable than a 50/50 mix:

  • Less settling over time

  • Better for grading and base layers

  • Slightly lower in organic content, but still nutrient-rich

50/50 mixes are lighter and better for planting-focused applications, while 70/30 is better for structure + support.


Is this good for growing plants?

Yes — it contains green waste compost for nutrients and supports:

  • Trees and shrubs

  • General landscaping plants

  • Planting mounds

For vegetables or delicate plants, consider adding a top layer of planting mix for optimal results.


Does this soil contain rocks or debris?

Yes — this is a bulk screened soil, not a fine sifted garden mix. It may contain: Small rocks. Wood fragments, Organic debris. This is normal and expected in landscape-grade soil.

Heavy Weight Topsoil 70/30 Mix

SKU: BLND-SOL-HVTPSL-103
$68.00Price
$68.00 per 1 Yard
Quantity
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