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Filling Deep Raised Beds: Using Subsoil Fillers and Quality Topsoil Blends

Q: I built raised garden beds needing backfill before garden soil. Max depth 20 inches, min 10 inches. How deep to backfill and how deep for garden soil?

Plant roots only grow in the top 10 inches of soil. Fill the bottom with cinderblocks, bricks, or anything to take up space. Fill up to 10 inches below the top edge.

Fill dirt is fine for bottom but avoid heavy clay—it interferes with drainage.

For subsoil and topsoil, several Atlanta landscape material yards mix and deliver soil. They can blend sandy loam with worm castings or chicken manure for rich soil. Soil3 also delivers custom compost.

About Gardening: Fixing Waterlogged Raised Beds: Did You Include Drainage?; Calculating Soil Volume for Raised Beds; Soil Mixes for Raised Beds on Concrete: Do You Need Ground Soil?; Raised Bed Tomato Cultivation: Soil Preparation and Planting Methods; Raised Garden Beds: The Smart Way to Grow More with Less Effort; 9 Reasons to Garden in Raised Beds; Best Bagged Soils for Filling Raised Garden Beds: Product Recommendations; Building Raised Vegetable Beds: Plans and Soil Mix; Best Soil for Raised Beds: Skip Bagged Mixes, Go Bulk; Raised Bed Soil Settling: Plant Now, Top Off Later

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