Raised Bed System
Multiple raised beds laid out as a vegetable garden or allotment system — sizing, path widths, durable species and a path-and-bed module that scales from one bed to twenty.
What you'll need
Materials
- Boards or sleepers, corner posts or screw-together corners, stainless screws, weed membrane for path bases, woodchip or gravel for paths, compost mix for beds.
Tools
- Drill/driver, mitre or hand saw, spirit level, tape measure, spade for ground prep, optional weed membrane stapler.
Material complexity: Low
Buy boards in lengths that minimise cuts — 2.4m boards perfectly suit 1200/2400 bed dimensions.
Main risk: Beds wider than arm's reach with paths too narrow for tools — the system becomes hard to actually use within a season.
Tips & traps
- Beds wider than 1200mm — can't reach the middle.
- Skimpy paths — wheelbarrow won't pass.
- No drainage detail at the base — beds become bogs in winter.
- Using single 25mm boards on long runs — they bow as soil swells.
- Random bed sizes — kills the visual order and complicates crop rotation.
Planning & timber detail
Why build this?
A modular raised-bed system transforms a patch of lawn into a productive kitchen garden. Built on a planned grid with proper path widths, it scales cleanly from 2 beds to 20, lasts a decade with minimal maintenance, and makes growing your own food genuinely practical rather than a chore.
Where it works best
Level or terraced ground with reasonable sun (6+ hours daily for veg). Allow space for paths AND for sitting/working AROUND the beds — most first-time gardens are over-bedded and under-pathed.
Planning notes
Plan the WHOLE system before building one bed — bed layout, path widths, water access, compost bin location. Single isolated beds tend to grow into messy clusters; a planned system stays organised. Orient beds north-south so plants don't shade each other.
Typical sizes
1200mm wide is the maximum reachable from one side (without stepping in); 600mm wide if accessed from both sides. 450mm height is comfortable kneeling; 750mm is comfortable standing. Path widths: 600mm minimum, 900mm if a wheelbarrow goes through.
Suitable timber options
Treated redwood is the scale-friendly default — multiple beds get expensive in oak. Larch is a halfway point that lasts longer than treated redwood. Use oak sleepers for one or two showpiece beds if budget allows.
Fixing and finishing
Screw from inside so heads are hidden. Galvanised or stainless. Avoid copper-based treated timber if growing food directly against the wood — modern treatments are generally safe but check the product.
For a modular system: standardise on one bed size and one path width. Cut all boards to length in one batch. Assemble corners with vertical posts (47×47mm or similar) inside the corner for screw bite and stiffness.
Maintenance
Top up beds annually as compost settles. Replace individual boards as needed — system design lets you swap one without rebuilding everything.
Lift and replace any board that fails individually. The system is its own spare-parts kit.
Timber behaviour
Durability
UC4 for timber in soil; UC3 if isolated by membrane and gravel. Treated redwood at this scale is the practical default.
Movement
Long boards on a single bed will bow if not corner-supported. Use intermediate posts every 1.2m on beds longer than 2.4m to prevent bellying as wet soil swells the timber.
Go deeper
Get the Timber Buying Companion
An 8-page practical guide to choosing better boards, avoiding waste and spotting common timber problems before you buy.