Gardeners’ World, 9pm, BBC2

THIS week, Monty Don plants a new bed of irises at Longmeadow, before turning the spotlight on pelargoniums. Elsewhere, Nick Bailey brightens up a dreary corner and offers tips on plants that will be happy in shady spaces, while Carol Klein marvels at an innovative garden in West Yorkshire. Plus, a visit to an Italianate idyll in Dorset.