Dating back to the mid 19th century, Mount Pleasant's formal garden design follows the Colonial Revival style, which relied heavily on boxwood borders and terraced land forms. Jacob Giles, the first owner of the estate and garden's designer, was heavily influenced by formal terraced European gardens, a popular style of the time. The man-made terraces housed elaborate gardens, presumably grown in Mount Pleasant's own greenhouse, which no longer stands today.

In the front of the home, a tall boxwood allee originally led guests directly to the front lawn. Portions of the allee can be seen from Bulle Rock Parkway directly across from the mansion.

In the rear of the house, a brick path and staircase leads visitors down levels of terraces from the lawn to the planting beds, once filled with peonies and day lilies. Continuing down the path, visitors would come upon a pool ringed with boxwoods and dotted with narcissus, flanked by two sycamore trees. Hollies, magnolias, cedars, and Japanese maples are a few of the trees that pepper the landscape with shade.

The gardens were so noteworthy that the first Federated Garden Clubs of Maryland included Mount Pleasant on their House and Garden Pilgrimage in 1930.

Mount Pleasant's 1360 acres were neighbored by Mark Pringle's 600 acre Bloomsbury estate to the south, whose mansion, built in 1808, sat where the current activity center sits today on Lewis Lane. A property marker identifying the dividing line, with the initials "M.P." still stands today, over 200 years later. 

In the early 20th century, care was taken to repair the farmland and improve the orchards. In the later half of the 20th century, the property was owned by Earl G. Weber, Sr. and his wife, who ran Weber's Cider Farm. Inspired by European orchards, they created a tree rental program where members of the public could rent a tree for  $30 and pick the apples when they were ripe.