Dimensions that work
- Width: 3–4 feet so you can reach the center without stepping in the soil
- Length: 8 feet is common because lumber is sold that way
- Soil depth: see how deep a raised bed should be
Materials
| Material | Look for | Tradeoff |
|---|---|---|
| Cedar or other rot-resistant wood | Board thickness; thin “kits” flex | Higher cost, finite lifespan |
| Untreated pine | Cheap and available | Shorter life in wet climates |
| Metal kits | Gauge (thickness) and interior coatings | Heats more in full sun; check bowing |
| Composite / plastic | UV rating and structural ribs | Quality varies widely |
Avoid treating interior faces with random deck stains unless the product is labeled for food-garden use. After you pick a size, calculate soil — the dirt usually costs more than the box.
Frequently asked questions
Is pressure-treated lumber safe?
Modern residential treated lumber is not the old CCA formula. Whether you want it against vegetable soil is a personal and regional judgment; many gardeners still prefer untreated cedar or a liner. This site does not issue a safety certification.