Sand Dune Revegetation

Local gardening enthusiasts Tim and Jan Sintes from SouthShore have been working on stabilising nearby sand dunes, which if left unchecked would swamp their property. Over the last eight years Jan and Tim have been replanting the sand dunes on their property with native species. About three years ago they started using extensive amounts of old carpet to act as a weed suppressant, and which also stabilises the dunes while new plants grow. The carpet suppresses and kills the maram grass, which then rots down to compost the native plants planted through the carpet.

Typical sand dune area	Huge area covered in carpet	Carpet covering the maram grass	New plantings in the carpet
Six months later	Rotted maram grass acts as compost, providing nutrients & retaining moisture for the plants.	You can just see the old carpet in this garden.	A shadehouse where once there was only sand
	A flax garden being established		A stream of shells

Weed mats and carpet provide many purposes (additional information courtesy of Alan Leckie from Forest research of Canterbury University):

• They suppress weeds that compete for water, nutrients, soil, and light
• They reduce the chances of weed seeds, present in the upper soil profile from germinating and also volunteer seeds   from colonising soil around the planted tree
• They can channel rainwater towards the stem of the plant
• They reduce the evaporation of rainfall from the soil, by shutting out direct radiation from the soil surface
• They mark the position of the plant, therefore reducing the chances of being accidentally stood on
• Woollen mats also contain some nutrients that plants use. The major plant nutrient Nitrogen can be found in high quantities and sulphur is also present. These nutrients need to be transformed from plant unavailable to plant available and this may take some years. This transformation occurs as the carpet breaks down
• The mats may also provide refuge to invertebrates and other soil dwelling animals such as worms, reptiles, and slugs