Planting a Dry Stone Wall
Rugged Natural Beauty
If you lack the space for a formal rock garden, but long for a display of alpine plants and flowers, a dry stone wall is the ideal solution. The combination of natural stone and colourful mountain flowers brings out the best of both.
The first dry stone walls were probably created as farmers clearing fields piled rocks and gravel on the borders of their land. These walls proved perfect habitats for alpine plants, and rock gardeners noticed that this combination of beauty and utility could be re-created in the garden.
Building a dry stone wall is a fairly simple way of making a dramatic improvement to the look of your garden. A beautifully crafted wall is a work of art within itself.
Where to Build?
The right location for a dry stone wall depends on the size and shape of your garden. Anywhere that a retaining wall is needed in front of a bank or along a drive – is perfect. You can also make a free-standing dry stone wall, but this takes up a lot more space.
Flowers and shrubs planted on the top of the dry stone wall should be compact with shallow roots. This helps to limit competition with other plants lower in the wall. Saxifrages and Androsaces are ideal plants for this positions.
If you live in or near the countryside, try to get in touch with local farmers to see if they will let you take rocks as you need from their land. Remember that you must always ask their permission first.
If this does not prove successful, or if you live in a city, check with stone-masons and quarries in your area. Both may have discards that they will let you take away.
The Right Rocks
The best rocks for building a dry stone will have a flattened shape. They should also be small and light enough for one person to lift without too much effort. Sandstone or limestone are rocks traditionally used to build dry stone walls but shale is also suitable.
If you use limestone for your wall, be sure to choose plants that tolerate lime. Plants that are lime-intolerant, such as summer-flowering heath, are not suited to limestone walls.
All dry stone walls need to be broader at the bottom than the top to give them stability. The size of this slope varies according to the finished height of the wall. Low walls should slope back at least 30cm for every 1.5m of rise; high walls need to slope back roughly 50cm for every 1.5m.
Before you start to build the wall, prepare a mixture of topsoil, compost, coarse sand and fine gravel. Have the alpine plants you have chosen ready when you begin construction, so that they are ready to insert into crevices as you build the wall layer by layer.
Dry stone walling is a traditional craft that is still practised by specialists in many parts of Britain. If you are not confident of you ability to build a dry stone wall in your garden, or would like to improve your skills, contact a local conservation group. Many such groups run courses in building dry stone walls in the countryside.
You can also plant up existing dry stone walls in the same way, adding small plants to crevices and cracks.