The current study examined the effect of an indoor simulated garden installation that included visual, auditory, and olfactory stimuli on resident well-being, compared to the effect elicited by a reminiscence installation and a control no-installation condition. A quasi-experimental ABA design was used (i.e., two intervention conditions plus a wait-list control condition). A survey instrument was administered to nursing home residents (N = 33) at three time points (pre-, during, and post intervention) over an 8-week period, which measured mood, behavior, health, and social interaction. Additionally, staff reports (N = 24) were collected. Both the nature-based and non-nature-based installations led to enhanced well-being and significantly more social benefits for residents because of their novel and aesthetic appeal, compared with the control condition. Residents in the nature-based installation condition reported more satisfaction with their living environment during the intervention phase than those in the comparison conditions. The results show that an indoor garden simulation is a relatively inexpensive way to transform a disused indoor area of an aged-care facility for the benefit of residents and staff.