Waste and Resources Action Plan (WRAP)

The primary aim of this study is to evaluate the use of a compost derived from kerbside collected garden waste on winter wheat The evaluation will compare the compost against conventionally applied inorganic fertilisers both individually and by substituting for part of the nutrient requirement normally supplied by inorganic fertilisers. The evaluation will assess crop yield and quality, changes in soil structure, nutrient content and organic matter as well the relative costs of production. This will be delivered as a report to include the statistically analysed trial data and a cost:benefit analysis from both an economic and environmental perspective.

Waste and Resources Action Plan (WRAP) Project PBD7-201

This project is to demonstrate that recycled gypsum from waste plasterboard can be an effective soil conditioner on commercial arable farms.

Application of gypsum to soils, particularly heavy soils, has previously been found to improve soil structure, and there are also indications it can improve the efficiency of uptake of nutrients and minerals by plants. These effects have both economic and environmental benefits through extending the weather windows in which the land can be worked, improved plant health, and allowing more efficient use of inorganic fertilisers.

The increasing cost of virgin mineral gypsum has deterred many farmers from its use. Recycled gypsum is not fundamentally different from mineral gypsum but can be obtained at much lower cost.

This project will compare recycled gypsum derived from waste plasterboard against virgin mineral gypsum to demonstrate that the beneficial effects it can provide are at least equivalent. This will be rigorously evaluated through two sets of controlled field trials, one on potatoes between February and November 2006 and the other on winter wheat between September 2006 and August 2007.

In addition, the trials will aim to establish the extent to which recycled gypsum can improve the efficiency of nutrient uptake. These will include assessments of crop yield and quality, changes in soil structure and nutrient status, as well as the relative costs of production. A scaled programme of inorganic fertilisers will be used in the trials to enable the results to be directly applied to commercial farms.