How much does a raised bed cost?

A 4x8 cedar bed costs $160-310 total including soil.

Gardening

Raised Bed Calculator

Calculate all materials needed to build a raised garden bed: lumber, corner posts, screws, soil volume, and estimated cost.

Quick Answer

A standard 4×8 foot raised bed at 12" tall requires four 8-foot boards, four 4-foot boards, 4 corner posts, about 24 screws, and 32 cubic feet of soil. Typical cost: $50-80 for lumber and $80-160 for soil.

Bed Dimensions

Length (feet)

Width (feet)

Height (inches)

Board Width (inches)

6" or 12" typical

Lumber $/8ft board

Soil $/2cu ft bag

Materials List

Material	Quantity	Details
Long side boards	4	8 ft each
Short side boards	4	4 ft each
Corner posts (4x4)	4	1.0 ft each
Deck screws (3")	24	exterior rated
Soil / Mix	32.0 ft³	16 bags (2 cu ft)

$48.00

Lumber Cost

$80.00

Soil Cost

$128.00

Estimated Total

About This Tool

The Raised Bed Calculator generates a complete materials list for building a raised garden bed from scratch. Enter your desired dimensions and it calculates the lumber, corner posts, screws, and soil needed, along with cost estimates. This saves trips to the hardware store and prevents buying too much or too little material.

Choosing Lumber

Cedar and redwood are the best choices for raised beds because they naturally resist rot and insects without chemical treatment. They last 10-20 years in ground contact. Untreated pine is cheaper but may only last 3-5 years. Modern pressure-treated lumber (ACQ treatment) is considered safe for vegetable gardens by the EPA, though some gardeners prefer to avoid it. Never use old CCA-treated lumber (pre-2004) near food gardens.

Ideal Bed Dimensions

Keep beds 4 feet wide or narrower so you can reach the center from either side without stepping in the soil. Length can be anything, but 8 feet matches standard lumber lengths and minimizes waste. Height of 12 inches works for most crops. Go taller (18-24 inches) if building on concrete, for accessibility, or for deep-rooted crops.

Assembly Tips

Pre-drill screw holes to prevent splitting. Use 3-inch exterior deck screws or structural screws, not drywall screws which rust. Place the bed on level ground and check with a level before filling with soil. For beds longer than 8 feet, add a mid-span support brace to prevent bowing when the soil is wet and heavy.

Cost Saving Tips

Buy soil in bulk rather than bags if you need more than a cubic yard. Ask local tree companies for free wood chips as mulch. Use hugelkultur (burying logs and branches in the bottom third) to reduce the amount of soil needed. Some cities offer free compost from municipal composting programs. Check local lumber yards for better prices than big box stores.

Frequently Asked Questions

What is the best wood for raised beds?

Cedar is the top choice for durability and natural rot resistance. It lasts 10-20 years and looks beautiful. Redwood is equally good but harder to find outside the West Coast. For budget builds, untreated Douglas fir or hemlock works but needs replacement in 3-5 years. Modern pressure-treated lumber is safe for food gardens.

How much does it cost to build a raised bed?

A basic 4x8 cedar raised bed costs $80-150 for lumber and $80-160 for soil, totaling $160-310. Pine is cheaper at $40-70 for lumber. Using bulk soil instead of bags saves significantly on larger projects. Hardware (screws, landscape fabric) adds $10-20.

Do I need to line the bottom of a raised bed?

On soil: no lining is needed. Cardboard or newspaper on the bottom suppresses weeds and breaks down over time. On concrete or a deck: use landscape fabric to prevent soil from washing out while allowing drainage. Never use plastic sheeting on the bottom as it prevents drainage and causes waterlogging.

How tall should a raised bed be?

12 inches is standard and works for most vegetables. Use 6-8 inches for shallow-rooted crops on top of good native soil. Go 18-24 inches for accessibility (less bending), building on concrete, or deep-rooted crops like potatoes. Taller beds cost more and need more soil but offer better drainage and warmer soil in spring.

Should I put rocks in the bottom for drainage?

No. This is a persistent myth. Rocks actually create a perched water table that makes drainage worse, not better. Fill the entire bed with quality soil mix. If you want to save on soil volume, use the hugelkultur method: fill the bottom third with logs, branches, and leaves, then top with soil.

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