Fleece is permeable to water
Raised beds made of wood in particular need good moisture protection, otherwise they will rot after a few years and have to be replaced. It is important to protect the material from moisture from the soil and from the filler material. For this purpose, you usually use pond or bubble wrap, which is impermeable to water and thus offers reliable protection. Instead, using various nonwovens, such as those used in the garden, is usually not useful. Fleece is often water-permeable and therefore cannot fulfill the hoped-for purpose - this is especially true for weed fleece. (€ 28.90 at Amazon *) An exception, however, is special raised bed fleece, which is made of polypropylene or PET and is usually sold as an individually cut material on rolls.
- Which is better for the raised bed: pond liner or bubble liner?
- Is there a foil for the raised bed without harmful substances?
- Can you build a raised bed without a foil?
Protecting raised beds from moisture - what options are there?
In addition to waterproof fleece or foil, there are other ways to protect the sensitive material of a wooden raised bed from moisture. For example, you can build a raised bed made of natural or concrete stones and clad it on the outside with wood. Such a raised bed is particularly stable and durable, but also quite complex to manufacture and cost-intensive.
Painting a raised bed does not protect against moisture
On the other hand, special paints, varnishes or glazes with which the wood is treated are not very suitable as protection against moisture. Such a protective paint is not sufficient on its own; further measures such as a fleece or a film would have to be added. In addition, non-toxic colors should be chosen, especially if the finished raised bed will later be used for growing vegetables or fruit.
Weed protection fleece as a base for the raised bed - useful?
However, a fleece can not only be used to protect against moisture - provided it is impermeable to water - it can also be positioned in difficult locations in the form of a weed protection fleece on the open ground of the raised bed and thus prevent stubborn root weeds from penetrating. In contrast to the moisture protection fleece, such a weed fleece must be water-permeable so that excess rain and irrigation water can flow out of the raised bed.
Plant bags made of fleece are particularly well suited for the balcony or terrace, which can be easily filled and planted and finally folded up over the winter and easily stowed away.