Size: The size can vary, however, consideration must be given to whether or not the container needs to be moved to a protected winter location (freezing soil and the water it contains may damage containers by misshaping or cracking).
Light: Containers may be placed in full sun, partial shade or full shade with the appropriate plant materials.
Water: Native plants in a container will be exposed to much harsher conditions than in a garden bed, so extra watering may be required. Morning watering is preferred.
Fertilizer: Native plants normally do not require fertilizer, but if they are to remain in the container throughout the growing season with annuals, then fertilizer may be applied either every two weeks with a fast-acting fertilizer or every six to eight weeks with a slow release fertilizer. Fertilizer with three equal numbers is recommended, such as 10-10-10.
Exposure: Keep in mind that containers are often exposed to the elements on all sides, and plant materials are subject to much higher or lower temperatures than they would encounter in a garden bed. Extreme temperatures can damage roots, eventually weakening the plants and possibly causing death. Be vigilant and remove the plant(s) to a garden bed at the first signs of stress.
Soil: Although native plants grow in a variety of soil types, it is advisable to use commercial container mix (soilless), especially if combining native plants with annuals or nonnative perennials.
Planting Materials: Research your native plant choices before purchase. Consider light and water requirements, height, color, length of bloom time, etc. Plan to move your native plants to a garden bed when blooming fades or plants becomes uninteresting. This method is a good way to introduce and intermingle native plants in your perennial garden. Many native plants are interesting throughout the growing season with persistent seed heads, unusual scents and intriguing growth habits, not to mention their attractiveness to wildlife. See list.
Design: A 10-12 inch container will hold three medium plants (from four- to six-inch pots at purchase). The rule of thumb is to select one tall (upright) plant as the focal point (“the thriller”); one medium height plant with a mounding growth habit (“the filler”); and one trailing plant (“the spiller”) to flow over the side of the container.
Planting and Maintenance: Fill the container to within one to two inches from the top with soilless container mix. Add fertilizer according to directions on the package and mix with the soil. Position potted plants until you are satisfied with the “look.” Dig the holes deep enough so that the bud/crown (where stem meets root) is about one inch below the soil line. Gently compress the soil around the plant. Water thoroughly and continue watering when necessary. Most native plants should not be deadheaded, because of interesting seed heads. However, use your own discretion. If a native plant becomes faded or uninteresting, transplant it into your perennial bed where it will provide you with years of beauty as its roots lengthen. At the end of the growing season, all remaining potted native plants should be transplanted to the garden bed. Do not try to overwinter the native plants in the pot or indoors. Their root systems need plenty of room to thrive and probably will not survive the cramped quarters of a pot for another year.