81%
more bouquets meant more elderly recipients reduced their depression scores
Exact: 81% vs 64% vs 57%
Receiving two flower bouquets was associated with the highest rate of depression score reduction in elderly participants
On the DES depression subscale (sad, shame, guilt, self-hostility), a dose-response pattern emerged: two bouquets produced the greatest improvement, followed by one bouquet, while the no-flower group showed roughly chance-level fluctuation. The difference between groups was statistically significant (p = 0.05).
On the DES depression score (sad, shame, guilt, and self-hostility) score, 81% of participants who received both bouquets, as well as 64% of participants who received one bouquet, had lower depression scores than they did at the pretest. Only 57% of participants who had not received flowers (i.e., about half the 'no flowers group' increased and half decreased their scores, as expected by chance).
Related findings
+0.10 SD
better overall cognitive function after ecological zone policy
NKEFZs implementation improved overall cognitive function by 0.0993 standard deviations
Jia Tang et al., 2025, Social Science & Medicine
24 sessions
length of the garden-based healing and learning program delivered to young adults with intellectual disabilities
A 24-session, three-month garden-based program improved psychological stability, social relationships, and individual capabilities in YAwID
Dohun Kim et al., 2025, International Journal of Environmental Research and Public Health
+0.5
greater self-reported attentiveness with indoor plants present
Participants in the room with plants reported feeling 0.5 points more attentive (on a 1–5 scale) after completing the task
Virginia I. Lohr et al., 1996, Journal of Environmental Horticulture
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