The film is semi biographical and so it was important to film on location where John Keats actually lived. However, Jane Campion made compromises to ensure the film was accurate but also practical to film considering budget.
John Keats moved to Wentworth Place in 1818. You can see at that link the house is white and looks like an everyday house for the early 19th century. So to duplicate the look the movie was actually filmed at Hyde House and Estate. A similar style house that was better filming location. To increase the appeal of the house power washers were used to clean the exterior of the house and concrete surrounds. The best petrol-gas powered portable power washers were hired and used.
In addition to filming on location in the house “some filming also took place at Elstree Studios.”
All in all the critical reception was high and much of that must be attributed to the Directors choice of filming locations and diligence in presenting an accurate portray of early 19th century living in England.