Money doesn't grow on trees, but now plastic does. Monsanto researchers have engineered thalecress and oilseed rape plants to produce a biodegradable plastic nicknamed PHBV. The researchers describe their work in the current Nature Biotechnology. It builds on earlier work which used bacteria to produce PHBV. Bacterially produced plastics could be formed but at five times the cost of conventional processing using petroleum. Now researchers have shown that plants, too, can be pressed into plastics manufacture, yielding 3 per cent of dry weight after processing, still uneconomic but offering possibilities for the future.