Wood, stone, metal or would you rather plastic? Many different materials can be used to build a raised bed. Some of them are very durable, while others need to be protected from damaging external influences. However, with a well thought-out construction you can significantly increase the life expectancy of a raised bed.
How should a raised bed be constructed to be durable?
For a long-lasting raised bed construction, wooden raised beds should be covered with foil and placed on paving stones or concrete. For stone raised beds, a concrete foundation and avoiding moisture gaps are important.
Always protect wood from moisture
Wood, for example, is extremely sensitive to moisture and begins to rot quickly as soon as moisture has settled in it. However, chemical wood protection for prevention is not a good idea, especially for a raised vegetable bed - the toxins contained therein would pass into the crops and their fruits and would therefore be eaten by them. However, it is better to resort to these measures:
- Always cover the inside of a wooden raised bed with studded or partial foil.
- Build the raised bed walls at a slight angle and overlap the slats.
- This allows rainwater to drain away more quickly - and snails don't get into the bed.
- Do not place the raised bed directly on the ground - the wood will soak up moisture from the ground.
- It is better to place the corner posts or edges on paving stones or similar.
- Alternatively, you can also encase the corner posts in concrete.
- The top edges should also be slightly beveled to allow rainwater to drain away.
Choosing the right type of wood
Choosing the right type of wood can also significantly increase the lifespan of the raised bed. Hardwoods such as oak, Douglas fir, larch etc. are extremely robust and also have the useful property of absorbing only a small amount of moisture from the environment.
Stone raised beds: dry stone wall or mortared wall?
Raised beds made of stone are generally made of a very robust and durable material. Nevertheless, careful construction is required so that you can really enjoy your mini garden for a long time. Stone walls can be built using dry construction (i.e. without connecting mortar) or in the form of a mortared wall. Especially with the latter, it is important that you do not leave any gaps in the mortar or in the stones used: Moisture can penetrate here, which can freeze during the cold season and thus gradually destroy the stone.
Tip
No raised bed, no matter how sturdily constructed, will last long if the subsoil is not right. A good, solid foundation is the foundation of any long-lasting raised bed. For wooden raised beds, solid, level surfaces (and if necessary filled with gravel) are usually sufficient - stone raised beds, on the other hand, often require a concrete foundation.
