Mr. Richter, the ACS commissioner, said the campaign is part of a push by the city to find foster-care parents with more education and resources as well.
Peter Decaro and Kevin Leavy, a Brooklyn couple who became fosterparents to a 2-year-old girl and a 17-month-old boy in December, said they were surprised to find the foster care agency they worked with encouraging.
The sensory garden was built near the self-contained bungalow where Aaron lives in his fosterparents back gaden because the smells are supposed to be therapeutic for his condition.