Homes and businesses lose heat through air infiltration, heat conduction and radiation transmission.
To reduce air infiltration, properly positioning vegetation around homes and businesses can help slow wind velocities.
To reduce heat conduction, layer the vegetation close to and on exterior walls to trap air. This will serve as an pseudo-insulation for exterior surfaces.
Lastly, radiation transmission takes place mostly through windows, so blocking windows with vegetation will decrease heat loss from the home. However, if the window faces towards the winter sun (south), vegetation may block out sunlight that would warm the house.