A window planter is a plant container made to fit on the outside of a home underneath windows. It is also called a flower box, as many window planters are used to hold flowers and are rectangular, shallow and box-shaped. A window planter, or window box, containing plants or flowers can be easy to water and care for if it is either at a home's main level or can be accessed from the inside of the window.
While rocks or pieces of broken pottery may be used for ground level planters to allow for drainage when watering plants or flowers, these drainage materials are too heavy for a window planter. Window planters hang below windows and rocks and clay tend to weigh the planter down too much. Instead, charcoal or lightweight foam packing materials known as "peanuts" may be used as a drainage system for a window planter.
Depending on the climate, a wide range of flowers and plants may be grown in window boxes. A mix of herbs, flowers and even vegetables can create an interesting display of colors, shapes and textures in window planters. It's important to note that a window planter is different from a window cage. Window cages are the same shape as window planters, but they are made of a very openwork type of design that can't contain soil. A window cage is likely to be metal and it only holds potted flowers and plants.
Metal window planters can add a contemporary appeal to homes. A wooden window planter is a classic look that can look very charming when filled with plants and flowers. A wooden window box may make a good project for the beginning woodworker since only straight lines and simple construction are required. The wood may be painted or stained to coordinate with the home's exterior look.
Some homeowners like to use window planters made from synthetic materials such as vinyl. Vinyl is short for its full name, polyvinylchloride (PVC). Vinyl is a strong material formed from chlorine and ethylene and used for many household items. A vinyl window planter won’t rust or rot, but many find that it lacks the natural charm of metal or wood window planters.