Garden guide
How to Build a Raised Bed with Railway Sleepers
The short version
Two courses of sleepers (about 25–30cm high) suits almost everything you'd grow. Use full 2.4m sleepers for the long sides and cut or half sleepers for the ends, stagger the joints like brickwork, and fix each course to the one below with long timber screws.
Planning the size
Keep the bed no wider than 1.2m so you can reach the middle from both sides without stepping on the soil. Length is up to you — a 3m × 1.2m bed at two courses high is 16.8m of sleeper run, which works out to seven full 2.4m sleepers cut to fit.
Building it
Level the ground first — time spent here pays off on every course. Bed the first course on a thin mortar bed or compacted sand if the ground is uneven, then stagger the second course so joints don't line up. Drive 150mm timber screws down through each course into the one below, two per sleeper minimum.
Lining and filling
Line the inside faces with plastic (below soil level so it doesn't show) to keep damp soil off the timber and extend its life. Fill with topsoil for the bulk, then mix compost into the top 10–15cm — see our topsoil vs compost guide for why the combo beats an all-compost fill on price and structure.
Softwood, oak — and a creosote warning
New treated softwood sleepers are the sensible buy: 10–15 years of life at a fair price. Oak lasts 25+ years untreated but is heavy and dear. Avoid old reclaimed creosoted sleepers for veg beds — the chemicals can leach into soil. Our sleeper calculator prices full sleepers and halves and works out the cheapest mix for your bed size.