At Farm on the Hill our focus includes the following: Research into perennial food crops. Perennial food crops are crops that stay in the same place for many years, do not need annual replanting and therefore do not involve regular use of detrimental practices such as ploughing. Research into the production of sustainable fibres and natural dye plants. Fibre production is one of the biggest areas responsible for environmental damage, but is not often something considered within UK farming. Forest Gardening, a term coined to describe a multi layered cropping system modelled on nature.