Calcined Clay has become a popular soil amendment for all categories of indoor plants. It meters moisture in the adjacent soil to keep it from getting soggy or bone dry. Fired at super-high temperatures, its high porosity is ideal for effective drainage and aeration. Calcined Clay has become a popular soil amendment for all categories of indoor plants. It meters moisture in the adjacent soil to keep it from getting soggy or bone dry. Fired at super-high temperatures, its high porosity is ideal for effective drainage and aeration. Terrain is a garden and home brand deeply rooted in nature and plant life. From weather-ready planters and outdoor furniture to artisan-made wreaths and hand-poured candles, their curated product assortment explores the boundaries of life lived outside and in. With a globally conscious, locally influenced point of view, Terrain offers inspired seasonal solutions for creative living, gathering, and gardening.