A great article about gardening in preschools can be found here:
Gardening is a wonderful way to engage children and teach them about the natural world. Nature is beneficial for their development in many ways and it teaches them to respect the environment as well as come together as a community. At Kuwait Reggio Center, we have incorporated gardening into our curriculum. Students learn to grow their own vegetables and then sell them or use them in their own cooking.
A few of the ways that gardening is beneficial for young children are outlined below: