Complex sentence: He rented land abutting that of the Castle to farm, and on which to lay out trees and walks, and his niece Lady Hester Stanhope designed and managed the gardens and acted as his hostess.
Split into simpler sentences: He rented land abutting the Castle to farm, and on which to lay out trees and walks. His niece Lady Hester Stanhope designed and managed the gardens and acted as his hostess.