Lou and Andy

S3, E7: Alan and the team face their biggest challenge so far as they take on the smallest garden they have ever had to transform. Lou and Andy Webb have two children, four-year-old Harvey and two-year-old Megan who suffer from achromatopsia - a condition which means that they can only see in blurred black and white and are extremely sensitive to sunlight. Lou and Andy's garden is full of uneven surfaces and a derelict greenhouse, so Alan calls in his team. The first task is to create a shady environment for the kids in the form of a pergola, which proves to be a major construction project. David Domoney installs acoustic fencing to cut the noise from the nearby railway, and a special lighting system so that the kids can use the garden in the evenings. Katie Rushworth and Frances Tophill choose plants that will look beautiful and are suitable for the shady environment. Mum and Dad are not forgotten either, as one sunny corner of the plot is given over to seating and an entertainment area.