This year in the Drylands Department, we started work on a herb spiral in the Arboretum to demonstrate a water-efficient growing technique for dry areas. First initiated by our volunteer Ulrike, the herb spiral project had then been taken over by Giulia and Margaux – now we’re excited to say that the beautiful project is now finished!
Here in Almeria, the driest region in Europe, building such a spiral can present many benefits.
Efficient water usage
First, the spiral is designed in such a way that it retains the moisture at its base. This design allows a large variety of herbs to grow as it has both a drier zone at the top and a moist area at the bottom. Our herb spiral will then probably see plants that don’t drink much, like rosemary, oregano and thyme, grow at its top part. The water management of the spiral is such that no water is wasted. The runoff water is collected and absorbed by the thirsty plants positioned at the bottom of the spiral.
Adapted to microclimates
In the same way, the spiral’s design also helps the herbs to benefit from diverse microclimates due to the variety of positions allowed : sunny, sheltered and shady. The top part of the spiral will then be perfect to grow herbs like rosemary, sage and thyme that prefer a sunny position, while the bottom part of the spiral will fit better to shade-loving herbs such as mints.
Besides, the stones used to build the spiral retain heat absorbed during the day, keeping the spiral warm when temperatures drop at night. Retaining the heat can be really useful in a semi-arid climate, where we usually face huge temperature gaps between daytime and night time.
A unique garden feature
More than a practical tool that allows to grow a variety of herbs under the best conditions in a dry area, the herb spiral is also of aesthetic interest. Inspired by nature itself, the design of the spiral ramp is irresistible to the eye and draws it as a focal point in the garden. The stones used for our spiral are carefully chosen to be aesthetically pleasing to our visitors’ eyes.
We’re looking forward to reaping the benefits of our herb spiral in delicious, flavoursome dishes in the months to come!