Most gardeners advocate drainage with expanded clay in raised beds. We also belong to this group. You can find out in this article what the advantages of expanded clay drainage in raised vegetable beds are, when it is particularly recommended and what the filling should look like.
Is drainage with expanded clay useful in raised beds?
It makes sense to use expanded clay as drainage in raised beds. The material offers numerous advantages, with the main focus being thatexcess water drains away reliablyHowever, it is important to shorten the watering interval so that the soil in the vegetable bed does not dry out.
What are the advantages of drainage with expanded clay in raised beds?
Drainage with expanded clay has the following advantages in raised beds and also in other planters:
- water permeable, counteracts waterlogging
- chemically and biologically neutral, does not change the pH value in the substrate
- structurally stable, almost rot-proof and therefore extremely durable
- resistant to pests and fungi, reduces risk of infection of the respective plants
The latter aspect is particularly important in raised beds, as fruit and vegetables are primarily planted here.
For which types of raised beds is expanded clay drainage recommended?
Expanded clay drainage is primarily recommended for raised beds without direct contact with the ground, i.e. so-calledtable raised beds. But drainage with expanded clay is also advisable for beds on heavy, poorly permeable soils.
How do I properly design drainage with expanded clay in raised beds?
Fill the raised bed as follows:
- Line the raised bed with foil.
- Fill in an 8 to 10 cm high drainage layer made of expanded clay.
- Cover the drainage layer with garden fleece. This prevents the soil from being washed into the spaces between the expanded clay balls.
- Fill raised bed with nutrient topsoil or humus soil.
- Planting raised beds.
Tip
Critical voices about drainage with expanded clay in raised beds
There are also critical voices about expanded clay drainage in raised beds. This is because clay granules allow the irrigation water to drain away relatively quickly, so that the soil dries out more quickly, which in turn means that you have to water more often, otherwise the harvest could be poor. However, we believe that it is better to shorten the watering interval than risk waterlogging.