Gardeners can help lavender and rosemary flourish by mixing gravel into the soil around the plants, according to Amanda MacArthur from the Food Gardening Network.
Why Woody Herbs Differ
Most plants need feeding to support growth, and leafy herbs such as basil, mint or parsley will yield more flavoursome leaves if given nutrients at this time. Yet woody herbs like lavender or rosemary, which hail from dry climates, actually perform better in poor-quality soil.
The impact of fertiliser can prove too much for woody herbs, reducing their likelihood of surviving autumn as their delicate new growth struggles in the colder weather.
The Gravel Technique
MacArthur revealed a simple technique to help lavender and rosemary flourish by adding gravel to their soil during the summer months.
She said: "This may not be the first thing you think of as mulch, but herbs like rosemary that come from Mediterranean climates love the drainage and the heat that gravel offers.
"And since gravel isn't going to decompose, it's a good choice if your herb garden is also part of your landscape design."
Benefits of Gravel Mulch
Mulching is a simple but important gardening technique where material is spread around a plant for protection. During warmer months, plants are typically mulched with materials such as bark to help preserve moisture in the soil.
Yet, both lavender and rosemary dislike waterlogged soil, as it heightens their vulnerability to root rot and other fungal infections caused by excessive moisture.
Gravel helps drainage and bounces sunlight at the same time, which serves to heat the soil and replicate the dry, rocky environments these herbs naturally thrive in. The resulting soil is a healthier, more resilient environment that encourages stronger roots, tougher foliage, and greater flower production. It also boosts essential oil content, making lavender blooms more fragrant and rosemary leaves fuller, with a more intense flavour.
Whether you grow woody herbs in containers or the garden, introducing a little gravel can substantially enhance the growing conditions for lavender and rosemary.
