There is work to be done around and in the pond this week and Monty also begins planting out his dahlias. Adding zing to the month of May is the euphorbia and Carol Klein visits Oxford Botanic garden to view their extensive collection. Mark Lane is in Hackney finding out how a car wrecker's yard at the side of a Tudor National Trust property has been transformed into an award-winning garden used by the local community, while Adam Frost explains how to plant for structure in his herbaceous border. Rachel de Thame visits a garden which has opened to the public every year for 90 years for charity as part of the National Gardens Scheme, while Nick Bailey is in Devon, where he discovers how a pond plant has now escaped into the countryside and is invading waterways. And we reveal the final candidate for our Golden Jubilee plant and open the vote.