Planter box borders are particularly attractive around patios where flowers and plants are raised to the height of the planter. Larger box-shaped planters make it easier to direct the flow of traffic around the patio. In addition, using planter boxes as borders provides opportunities to elevate screening plants to hide or disguise less attractive views and provide privacy.
Measure your patio area. Place planters on a level, even surface to maximize usable patio flooring. When possible, arrange planters just off the patio. Draw the shape and dimensions of your patio on 1/4-inch graph paper indicating connecting areas such as house doors, steps, pathways, air conditioning units, trellises and step-downs.
Determine what type of border you would like to create with the planters. Larger planter boxes allow for more substantial plants. For areas that do not freeze in winter, you can plant large shrubs and trees in planter boxes. Planters that need to be wintered should be smaller so you can move them inside if necessary.
Select planter boxes 18 to 24 inches high for areas where you would like to use screening material. This will place foliage at approximately the same height as a person sitting on lawn furniture and will allow views to be screened. Add small trellis frames to the back of these planters to create further enclosure and privacy.
Use your patio plan to sketch the size of the planters you would like to use. Add the dimensions of existing patio furniture you want to keep and make sure there is ample room to pull chairs out from a dining table or to walk between furniture. Minimum distance to walk between furniture is 3 feet.
Select a planter style that has both large and small planters. Box shapes are often a good choice for straight borders. Use larger planters at screening areas or to mark the patio's entrance. Use smaller or lower planters to define the remaining border. Keep all planters level and even for a clean border appearance.
Place a thin layer of gravel on the bottoms of planters to aid drainage. Make sure planter bottoms have drainage holes. Add soil, fertilizers and other amenities for the types of plants you have selected. Plant your selections using a hand trowel and gardening gloves. The finish height of soil in the planter should be 1 to 2 inches below the top edge of the planter. Water new plants thoroughly.