In nature, plants occupy every imaginable niche on the planet. Not just restricted to forests and fields, they grow from cliff-side cracks (succulents), submerged swamplands (reeds) and will even grow right out of other plants (epiphytes). Since almost everything is a potential substrate for plant life, we can have fun with the quirky adaptability of plants by intentionally vegetating repurposed objects.
Basin-like objects makes a straightforward planting project: an old rowboat becomes a vegetable garden with a cargo net trellis; an outdated kitchen sink is just the right size for a few favorite herbs; an antique horse trough that still holds water could become a new aquatic garden. Rusty wheelbarrows, a wicker basket mounted on an old bicycle or a vintage chest of drawers are just a few of the many objects that are possible to plant. If the object doesn't have adequate drainage as it is, drill four ½-inch holes for every square foot of surface area to keep the plants from becoming waterlogged.
Above and Beyond
If you're up for a bit of a challenge, try playing with other forms of furniture. With a little ingenuity and access to power tools, almost any object can be modified to support plant life.
A partially hollow log can house plants like staghorn fern, which grows naturally on the side of trees. As an epiphyte, it does not require soil, living off of air and water only. An outdoor chimenea fireplace can erupt with plants from the top of its smokestack, as well as the hollow base where the flames once glowed. Vintage lamps and light fixtures (with their electrical innards removed) are also good candidates, offering an array of vertical and horizontal surfaces. Birdhouses, swing sets, mailboxes, bobsleds and shelving units are just a few of the other possibilities.
Modifying these objects to hold plants and soil often involves improvisation and extra hardware. Strips of reclaimed 'barn' wood or vintage architectural trim can be tacked on here or there to create pockets of soil. Wire mesh (hardware cloth) is useful to create containers on objects without flat sides, as it can flex to fit any shape. Bailing wire, sisal rope and an assortment of hooks, screws, clips and carabiners may all come in handy in the process. Often, an ordinary pot can simply sit on top of or be attached to the object in question.