The walled garden that is now part of the Haddon Lake House site is the larger of two walled gardens built of greensand by Thomas Haddon in the 1820's. This garden measures approximately 120' x 80' with the surrounding walls over 10 feet high in places. The walls are in remarkably good condition although in need of some remedial pointing in places. They were originally intended as a vinery, but later became the site for the production of choice flowers, fruit and vegetables.

The walled garden is being returned to its original use, with a pleasing and productive mix of fruit, flowers and vegetables forming a decorative 'potager'. The modern-day concrete paths overlay exactly the original simple path layout shown on the 1838/39 Whitwell Tithe Map.