Dry stone wall
In the countryside, dry stone walls are one of the best environments for wildlife. They provide miles of cover for creatures to move around from place to place, a vantage point for birds to perch where there are no trees, and nooks and crannies for insects, amphibians and small mammals to nest, overwinter, and hide.
They are host to many plants: tiny saxifrages sheltering in their crevices, heavy curtains of ivy sprawling across their backs, ferns and grasses tucked in at their feet and lichens and mosses studding their surfaces. Their central hollow is dry and snug and is home to everything from birds to bats and shrews to slow-worms.
In your garden
- Some of us might be lucky and already have dry stone boundaries in our gardens, but for the majority of us, the easiest way of incorporating this habitat into our gardens is as walls around raised beds. If this is not practical, just piling some rocks up together creates a similar environment. For the more ambitious, a dry stone and earth bank might be the answer.
- The gaps and crevices in a wall can be left to natural colonisation by plants, or given help by introducing small alpines, low-growing herbs such as thymes or perhaps saxifrages and sempervivums.
- Although many alpine plants have adapted to cope with hot, dry conditions, a wall situated in full sun all day will struggle to provide hospitable conditions for its residents. A north-facing wall might provide a more comfortable home for a wider range of plants and animals.
- Rocks and stones sourced locally blend better with the surroundings and the local soil.
- Because the walls act as ‘corridors’ for wildlife, leave a strip of unmown grass either side to provide more shelter.
- Build a dry stone and earth bank by piling stones up loosely to form a double-sided wall, leaving a gap in between. Build in layers of soil between the stones and in the centre, but leave gaps so that creatures can get in and out. Cover the top with wider stones, again filling any gaps with soil.
- On the whole, dry stone walls need little maintenance. Of course they can start to come apart and will then require rebuilding, but this is normally due to outside interference.
- Look out for trees and shrubs nearby that might damage the wall and keep any stray branches cut back.
- Encourage lichens and mosses to colonise a new wall quickly by painting it with, a mixture of yoghurt and manure – the British Lichen Society has further ingredient ideas and also suggests adding a little PVA glue to bind the mixture and make it stick.
- Extend the theme by planting up any cracks in steps or gaps in paving.