Learn the basics of creating a rock garden with Erin Doolittle. Rock gardens demand different design considerations, with special conditions and a different aesthetic. Erin will fill you in on what makes them unique and fun, a little history and a discussion of the different kinds of rock gardens. And, best of all, she’ll tell you how to create your own. Erin created a crevice garden, which is a variety of rock garden, at Tower Hill Botanic Garden after visiting rock gardens around the Northeast and in Colorado.