A recent study suggests scientific support for the emotional enjoyment we get from gardening. A specific bacteria in the soil may be a mood enhancer, and exposure to it can lift our spirits.
I always credited the joy of gardening to a combination of things: being in touch with our agrarian past (it just feels so right to dig in the soil); a connection to nature and the cycle of the seasons; the rewards we get from nurturing our plants; and the satisfaction of a completed job (even weeding) or a creative one. I think these are indeed psychological factors that can positively affect our physical chemistry, but it is intriguing to think that there may be a purely physical cause that can create this effect.
My gardening friend told me years ago that in winter she loves to go to a greenhouse and just smell the soil. I thought that was brilliant and have to say when I have done it the effects were immediate. The smell of fresh damp soil evoked memories of warmer gardening weather and the excitement to start again. Part of it, at least for me, is feeling the humidity we lack indoors in winter. But clearly Nancy was on to something big.
Here's a link to a story about the study. I would take issue with the term "dirt" since "soil" is what plants love and what we gardeners work to create for them. Ideally it is crumbly and teams with microbes and beneficial fungi. Sounds like a good subject for a separate post. Meanwhile, keep this trick in mind even if you can't get outside or work the land. It appears we can still benefit from just being around the soil.