Large stone or rock walls can sometimes dominate or overshadow the home landscape. The commanding presence of so much hard, cold stone can seem obtrusive and out of place.
While many homeowners may see just a looming structure, gardeners will see the crevices between the stones as an opportunity for a new planting project. Growing plants in a stone wall can soften and blend the stone into the landscape. Continue reading to learn more about gardening in retaining walls.
Gardening in Stone Walls
Living stone walls are commonly seen throughout Europe. In England, stone walls are considered the bones of the garden and are built with planting nooks for herbs or other plants. Planting flowers in a wall is an easy way to bring life to cold, dead stone and many plants will thrive in the unique microclimates of the wall’s crevices.
Plants growing in these planting nooks will appreciate the moisture and cool soil that stones can provide in the summer months. In the winter, these same crevices will stay warmer and quickly drain excess moisture away from plant roots, preventing rots or fungal diseases. Most experts would agree that the best way to create a living stone wall is by planting in the crevices as the wall is being built.
This method allows you to plan out specific plant pockets in the structure of the wall, place good growing media in the crevices and grow plants with larger root structures. Plants growing in a stone wall generally require a well-draining, sandy loam soil. The gravely soil fill that is oftentimes used in the construction of walls may drain too well, and usually lacks any nutrients to help the plants establish.
After the wall’s first level of stone is laid, rich growing media and plants are placed in the nooks created by the naturally irregular shape of the stones. Then a next level of stone is gently placed over the planting pockets, and the process is repeated until you reach your desired height of the wall.
Unfortunately, it is not always possible to plant in a stone wall as it is being built, but most existing stone walls can still be planted in. Poor soil can be removed from potential planting crevices with a long bladed trowel or garden knife and repacked with good growing media.
These designated planting nooks can either be planted with seeds or plants with small root structures. Take care when digging between rocks to not weaken the structure.
Ideas for Planting Flowers in a Wall
When gardening in retaining walls, it is best to avoid plants that develop large, strong root structures that could potentially damage the structure of the wall. The best plants for rock walls are alpine plants, succulents, and plants that are drought resistant.
Generally, they can thrive with small root structures and little water or nutrients. There are many plants that can grow well in the crevices of rock walls, so be sure to weed out any tree seedlings or other volunteers that may settle in between rocks. Below are some excellent plants for gardening in stone walls: