Recycle a hollow chunk of tree trunk, as Kansas City garden designer Kristopher Dabner did, and add a collection of dwarf plants to create a remarkable pocket-size forest scene. This 2-foot-long section of hollow trunk came from a damaged silver maple Kristopher had been forced to remove from his yard. With knotholes to promote drainage and a deep cavity in the center, it was a natural container. Before planting, he set the section of trunk on some large stones to facilitate viewing.
You don't need a tree trunk to create the same effect. Kristopher suggests an old dry sink on legs, a galvanized washtub, a large stone trough, or a spacious stone-look planter on a stand as alternatives. And you need not limit a miniature landscape to plants; consider including a little dry creek bed with gravel, for example.
Maintenance is minimal. Besides watering, you'll need to fertilize a couple of times a year. And if you plan to leave the planter exposed over winter, add extra insulation around it with straw or leaves and burlap. You'll also need to water the plants whenever winter temperatures climb to 40°F or higher.
Fill the openings at the planter's ends with small stacked flagstones. Form planting tiers by adding a stone retaining wall inside the planter, if you wish.
Line the bottom of the trunk with sphagnum moss. Fill the planter with well-draining potting mix for conifers.
Position and plant all plants. Enhance the planter with decorative rocks, especially if it is necessary to help it balance securely.