Comparing raised beds on sticker price alone is misleading, because lifespan varies so dramatically between materials. The comparison that actually matters is total cost divided by expected years of use — cost per season.
Untreated wood: cheap upfront, expensive over time
A basic untreated pine bed might cost the least at purchase, but at a 5-year average lifespan, the cost per season is often comparable to or higher than more durable options once you factor in eventual replacement.
Galvanized metal: higher upfront, lower per season
Metal beds cost more initially but at a 15-to-20-year lifespan, the cost per season is frequently the lowest of any material once amortized, particularly for gardeners planning to stay in one location long-term.
Fabric raised beds: the lowest commitment
Fabric grow bags and fabric-sided beds are the cheapest option and the shortest-lived — typically 2 to 4 seasons before the fabric degrades from UV exposure. They make the most sense for renters or gardeners testing a new bed location before committing to a permanent structure.
The deciding question
The right choice depends less on budget alone and more on how long you expect to garden in that exact spot. Under 3 years in one location favors fabric or basic wood; a decade or more favors metal or composite, where the higher upfront cost is spread across many more growing seasons.
True Cost Per Year of Use, Not Just Upfront Price
A cheap untreated pine bed costing $80 but lasting only 5 years works out to $16/year, while a $280 cedar bed lasting 12 years costs roughly $23/year — the pine option can actually be more cost-effective despite the higher replacement frequency, depending on your specific price points and patience for periodic rebuilding.
Fabric Beds: The Underrated Budget Option
Fabric grow bags and fabric raised beds cost a fraction of wood or metal options and offer genuinely excellent drainage and root-pruning benefits, though they lack the permanent, structured look of rigid materials and typically need replacing every 3-4 years as fabric degrades from UV exposure.