There’s a form of mental health counseling called horticultural therapy, which has been found to greatly relieve symptoms of depression and anxiety. And studies have shown that spending time in the forest is as useful as taking antidepressants. I recently read an article about “forest bathing,” which states, among other things:
… research shows that trees really do have healing powers. For one thing, they release antimicrobial essential oils, called phytoncides, that protect trees from germs and have a host of health benefits for people. The oils boost mood and immune system function; reduce blood pressure, heart rate, stress, anxiety, and confusion; improve sleep and creativity; and may even help fight cancer and depression.
https://qz.com/1208959/japanese-forest-medicine-is-the-art-of-using-nature-to-heal-yourself-wherever-you-are/
Of course, to get the benefits of gardening, I imagine you’d have to be working in a healthy environment. The soil in my neighbourhood — and many urban and suburban areas — is not very healthy. In fact, when I ran a soil test on my property upon moving in 3 years ago, the results showed that the soil was pretty much dead. Close to nothing left of anything beneficial. It’s much better now, but most of my neighbours do nothing to improve their soil. Instead, I see them using huge amounts of chemical fertilizers, pesticides, herbicides, and frequently replacing sick plants. If the plants are sick, chances are your soil is too.
"The United States is also a one-party state but, with typical American extravagance, they have two of them." -Julius Nyerere, First President of Tanzania