The Hawaii research station of the USDA (United States Department of Agriculture) has discovered that a spray solution of 1-2% caffeine kills large slugs and snails and repels them at concentrations as low as 0.1% (a cup of instant coffee contains about 0.05% caffeine). When soil was soaked with a 2% solution of caffeine, 92% of the snails left the soil after 48 hours or were found dead. Preliminary trials suggest that a 2% solution of caffeine does not damage the leaves of orchids and palms but does cause leaf-yellowing in ferns and bromeliads. Further trials might be undertaken by our growers in Italy? "The Garden" (RHS); "Nature" 2002, 417 pp 915-916. www.nature.com