Presenter Joe Swift takes the five remaining designers to the grounds of Sudeley Castle in Gloucestershire where they have to create formal gardens to impress RHS judge James Alexander-Sinclair and gold medal-winning garden designer Ann-Marie Powell. They have just four days to showcase their design skills, and their gardens must include a two-metre-high piece of topiary that they have shaped themselves from yew hedge.

The Great Chelsea Garden Challenge is a new competition for BBC2 with one of the biggest prizes in gardening - to design and build a garden on Main Avenue at the Chelsea Flower Show 2015. It's a prize that can launch one designer's career. In each episode, they will design, build, shop for and plant a show garden in a different style.

It's the final of The Great Chelsea Garden Challenge, a new competition for BBC2, and in this episode one designer is picked to design a garden on Main Avenue at the RHS Chelsea Flower Show 2015.

The pressure is on as the final three designers go to the RHS headquarters in Wisley, where they have five days and their biggest budget yet to create a show garden that will prove they are worthy of going to Chelsea. Mentored and advised by Joe Swift, the designers need to create flawless designs along with perfecting planting if they want to impress judges James Alexander-Sinclair and Ann-Marie Powell and win this life-changing opportunity.