No question, a raised bed like this is as practical as it is useful. It can also be placed in pretty much any place in the garden, as long as the plants planted on it get enough air in their location. After you have decided on a suitable variant, the only problem that remains is: What kind of surface does such a raised bed need? Can I also put it on the stone tiles of the terrace? In this article you will find the answers and a few suggestions.
Which substrate is best suited for a raised bed?
The optimal surface for a raised bed is level, firm and loose, ideally directly on the ground. Open soil allows access for microorganisms and earthworms as well as drainage of excess water. Raised beds without soil contact can be placed on stone or tiled surfaces if they drain well.
Raised bed should be placed directly on the ground
If you want to create a compost raised bed, you should plan it with open ground and contact with the earth - this means that the raised bed should stand directly on the ground. The reason for this is simple: Only in this way can all sorts of useful animals such as earthworms and other microorganisms that are important for making compost migrate from the soil into the raised bed and carry out their useful work there. Otherwise it will be difficult to compost the desired material, even if you can, for example, buy earthworms and put them out in the raised bed.
Does a raised bed have to have an open floor?
Of course, such a raised bed does not necessarily have to have an open floor and stand on bare earth, and that is not always possible. With a balcony raised bed, for example, you don't have this option at all, so you need other ideas. If the raised bed is only filled with soil (instead of compostable material), it is basically just a larger planter anyway and can also stand on stone, tiles or another surface.
No matter what surface: water must be able to drain away
But whether it is in contact with the ground or not: excess water, for example from the last downpour or from watering, should be able to drain away immediately. Otherwise, you will soon have a raised bog bed and grow your own swamp landscape. This is also why open soil and contact with loose, drained soil are so important: Here the water simply runs through the bed and seeps into the ground. If you have solid surfaces made of stone, tiles or wood, you will need to find other drainage options.
How to prepare the optimal surface for the raised bed
The optimal surface for a raised bed is evenly level and has firm, yet loose and permeable soil. It is best to prepare the substrate before building the bed as follows:
- Find a suitable location.
- Mark out the desired space for the raised bed using its dimensions.
- Dig a shallow pit of this size.
- Remove sod (pick up!), larger stones and pull out root weeds.
- Loosen the soil in the bed base a little.
- If necessary, line the area with a weed fleece (€19.00 on Amazon).
- Set up the raised bed.
- Lay rabbit wire in the bottom of the bed as a vole deterrent.
- Fill in the drainage layer as the first layer.
Both inorganic materials such as stones or organic materials such as coarse wood cuttings, larger branches and even tree stumps are suitable for the drainage layer. Make sure to fill in the spaces well. You can then fill the raised bed as desired.
Tip
Due to their greater weight, stone raised beds always require a firmer foundation, either made of pebbles and gravel or even concrete.
