Biochemical products (chemical products, fertilizers and soils) are once again making a recovery in the French garden market after years of decline. According to the GfK, sales in the first six months of 2007 rose by 7.02 per cent. The greatest increase was achieved by chemical products with growth of 19.5 per cent. DIY retailers notched up a 49.5 per cent sales increase in the month of April alone. The cold winter and damp spring were conducive to the spread of plant diseases and insect infestations.