VUA Interior
Technical Standards for VUA Interiors 
General- vehicular use area landscape design requirements for interiors require a careful consideration of permeability, plant growth, plant species and plant spacing.
Minimum Length- the length of most planting areas conform to the technical lengths of parking stalls, parking bays, length of travel lanes and linear relationships to other dimensions used in parking lot design. Minimum length of islands used to plant trees, shrubs and ground covers within parking lots is generally one parking space deep or eighteen (18) feet. Minimum length of islands used to preserve existing trees within parking lots is generally two parking stalls deep or thirty-six (36) feet.
Minimum Width- minimum width of vehicular use area plantings often are related to linear relationships and dimensions used in parking lot design. Minimum width for peninsulas is generally the same as a parking stall or nine and a half feet (9’-6”) while minimum width for islands is generally the width of several parking stalls. The minimum width of islands used to preserve existing trees within parking lots is generally two or more parking stalls deep or thirty-six (36) feet or wider if the size of the tree to be preserved warrants a wider width.
Minimum Area- is often a percentage of the total square footage of the vehicular use area including access roads, drop offs or any other surface are in which an automobile is free to move about. This percentage can vary from a minimum of five (5) percent to as much as twenty (20) percent. In some instances, minimum area for landscaping is tied to the number of parking spaces. A typical specification for this might be, one planting area the size of a parking stall (9.5’ x 19’) for each ten stalls provided.
Planting Area Character- planting sites are level and consistent with the slope of the surface pavement. In varied topographic settings retaining walls may be used to allow some naturalization in to the ground surface of the VUA.
Minimum Planting Area- per Class A tree shall be three hundred eighty (360) square feet, Class B tree shall be one hundred eighty (180) square feet, Class C tree shall be one hundred seventeen (117) square feet. Large container shrubs and B&B shrubs shall have a planting area as required by the landscape architect. Seven (7) gallon shrubs shall have an area a minimum of sixteen (16) square feet, three (3) gallon shrubs shall have a minimum area of four (4) square feet, one (1) gallon shrubs or ground covers shall have a minimum areas of two and one half (2.5) feet, and four (4) inch container stock shall have an area of one (1) square foot to grow-in.
Minimum Plant Bed Design- shall be composed of a raised planting bed a minimum of eight (8) inches deep over a scarified sub base or a sub base of structural soils. The plant bed shall be composed of an amended planting mixture, mulched with a minimum of two (2) inches of aged pine bark mulch and top dressed with one (1) inch of pine bark straw to prevent washing. Soil mix fertilizer amendment and chemical weed control composition shall be as the landscape architect may specify.
In parking lots where interior planting areas also function as storm water collection points, landscape beds will Be modified to include an eight (8) to twelve (12) inch French drain system with under ground pipe to carry storm water off to a parking lot detention.
Permeability- A minimum of twelve (12) percent of the total VUA interior must be planted with a mixture of shrubs and ground cover. Three (3) Class A tree or six (6) Class B trees must be planted every twenty-four (24) parking bays. Plantings within larger islands are preferred to spot planting plants within a rhythm of stalls or parking bays.
Spacing- per Class A trees are not recommended for VUA interiors but if used shall be forty (40) feet on center, Class B trees shall be spaced thirty (30) feet on center, Class C trees shall be spaced ten to fifteen (10 to 15) feet on center. Large container shrubs and B&B shrubs shall be planted as required by the landscape architect. Seven (7) gallon shrubs shall be spaced four to six (4-6) feet on center, three (3) gallon shrubs shall be spaced two to three (2-3) on center, one (1) gallon shrubs or ground covers shall be spaced eighteen to twenty-four (18-24) inches on center, and four (4) inch container stock shall be planted twelve (12) inches on center.
Planting Configuration- may be geometrically formal or informal as the landscape design plan shall so show and as the site may so suggest.
Minimum Plant Size- Class A shall be thirty (30) gallon, 3” caliper, 10-12’ tall, Class B trees shall be twenty-five (25) gallon, 2” caliper, 8-10’ tall, multi-trunk or standard. Class C trees shall be 4-6” tall at time of planting. B&B shrubs shall be thirty-six to forty-eight (48) inches tall upon planting, seven gallon shrubs shall be a minimum of thirty-six (36) inches tall at time of planting, three (3) gallon shrubs shall be a minimum of twenty-four (24) inches tall at time of planting and all one (1) gallon shrubs shall be a minimum of fifteen (15) inches tall at time of planting. All plants must conform to these standards or the general plant material size specifications of the American Nursery & Landscape Association which ever is greater.
Other-trees shall be staked with approved staking kit with ‘alligator bag’ attached first ninety (90) days. Tip pruning to shape after planting. All landscape beds shall be weed free and edged to prevent bed wash. Preserving trees within parking areas can be very complicated. This may require the submittal of a Tree Preservation Plan that takes into consideration the needs of trees(s) as well as construction cost.
