This acquisition follows William Sinclair’s recent purchase of Monro Horticulture’s Growing Success Organics company which specialises in garden care products.
William Sinclair directors say the latest acquisition will provide "growth potential for the future" and strengthen the company’s financial position in 2011.
They predict the previous purchase of Growing Success Organics to generate sales of around £3m in the year ended 30 September 2011.
Chief executive Bernard Burns said of the latest acquisition: "This acquisition re-affirms our commitment to supply premium products via our own extensive retail sales network to our customers – an essential part of providing the highest levels of customer service in the industry.
"William Sinclair is growing fast and we are intent on becoming the leading company in the horticulture sector – we will continue to consider further acquisition targets."