A dry stone wall built from natural stone is only half as beautiful and ecologically valuable if you leave it bare. The gaps in the dry stone walls should not be left empty, some plant species are suitable for planting here: these are species that tolerate the absence of water well, above all rock garden plants, for example houseleek (Sempervivum), stonecrop or orpine (Sedum) and saxifrages or rockfoils (Saxifraga). You can also choose from valuable flowering plants: the fragile earleaf bellflower or fairy’s-thimble (Campanula cochleariifolia) or the wood pink (Dianthus sylvestris) look beautiful.
Yellow corydalis (Corydalis lutea) or maidenhair spleenwort (Asplenium trichomanes) are recommended for the shady, northern side of the walls. Mouse-ear chickweed (Cerastium), candytuft (Iberis) and ivy-leaved toadflax (Cymbalaria muralis) can also grow in more humid parts.
Plants with drooping or cushion growth are ideal for the top of the walls, such as sweet alyssum (Alyssum) with its yellow color, moss phlox (Phlox subulata) with pink flowers, or purple rock cress (Aubrieta).
As early as the stone wall is being built, fill the gaps with some soil, press it down firmly, before the next row of stones is placed on it. The soil then serves as a medium and a growth-supporting material for the plants. Leave enough space for animals (beetles, lizards).
Stone walls can be filled with plants from March to September. Just as in nature, where plants occupy the existing gaps and cracks, in the same way here, plant stonecrop and similar species in tight spaces. Plants with root balls are an exception: plant them in the cavities of the wall during construction.