A feasibility study on indoor therapeutic horticulture to alleviate sleep and anxiety problems: The impact of plants and activity choice on its therapeutic effect.

Introduction: Therapeutic horticulture (TH) is increasingly being applied for sub-health or patient mental health care. Whether plant and activity type will affect TH's effectiveness is unclear.

Aim: To evaluate the feasibility of an indoor TH for alleviating the anxiety symptoms and sleeping problems of people with poor sleep quality, and explore the potential affection of plant and activity type on health benefits.

Method: Thirty subjects (all with sleep problems and half with anxiety problems) were randomly assigned to three groups to do horticultural activities with ornamental plants, general aromatic plants, or aromatic plants with reported mental health functions, respectively. Six indoor TH activities were then held sequentially within two weeks. Psychological scales, subjective feedback questionnaires, and physiological indicators were used as evaluation indexes before and after horticulture activities.

Results: The TH relieved subjects' sleep and anxiety problems and was particularly effective in alleviating anxiety among people with high anxiety levels. Using ornamental plants was more effective in relieving stress while functional aromatic plants performed better in sleep improvement and satisfaction to TH. Each horticultural activity could improve mood state but showed different effects on the vitality of the participants.

Conclusion: The above findings provided some basis for the potential benefits of selecting plants and activities based on psychological care needs in the development of TH plans. Future research that expands upon the current project is warranted. A larger sample size is beneficial for obtaining more powerful statistical results.