The Linear Garden: A Unique, Inexpensive, and Effective Way to Facilitate Plant Identification and Roadside Beautification

Abstract

here are over 2500 registeredbotanical gardens worldwidethat receive 200 million visi-torseveryyear(BotanicGardensCon-servation International, 2007). Asidefrom appealing toouraesthetic sense,botanic gardens and arboreta canbe used as outdoor teaching labora-tories. Numerous plant collectionsaffiliated with universities have beenintegrated into landscape design,landscape construction, herbaceousand woody plant identification, andturfgrass management curricula(Hamilton, 1999; Olsen et al.,1999; VanDerZanden and Cook,1999; Wilson et al., 2004). With theadvancements in web technology,these learning exercises can reachmuch broader audiences. For exam-ple, Wilson and Danielson (2005)created an interactive virtual plantidentification and use instrument fora native landscaping course, wherestudents can walk virtually through abotanicalgardenandself-selectplantsfor additional taxonomic detail.Long-term maintenance costsand availability of space are two com-mon issues encountered at universitygardens. The concept of a linear gar-den originated when existing univer-sity gardens were at maximum plantcapacity.Theneedtoteachstudentsalarge diversity of plant material in alimitedamountoftimeandspacepar-alleled local interest in roadside beau-tification. With minimal installationandmaintenancecosts,alineargardenwasestablishedalongthelengthoftheroadperpendiculartoentrancestoad-jacent University of Florida and U.S.Department of Agriculture facilities.A single grass strip (3 ft wide ·2426 ft long) was treated withherbicide and rotary-tilled with atractor. A vegetable bed press wasused to form 8-inch-tall beds, uponwhich a plastic mulch machine wasused to apply the single row of semi-permeable landscape fabric. To irri-gate the entire length of the bed withsimilar pressure, a 1.25-inch submainplastic tubing line was installed andconnected every 100 ft with 1-inchrisers and 25-psi pressure regulators.Drip emitters were used to deliverwater at 2 gal/h.Eight hundred seventeen plants(comprising 237 different taxa) wereplanted with spacing adjusted to ac-commodate their mature plant width.The garden was designed to showcasespecimen plants and display othercommon landscape plants used in thesouth-central Florida region withattention to foliage type and texture,flower color, plant size and form, andseasonality(Fig.1).Year-roundviewinginterest was obtained by using differentplant types, including 62 species oftrees,23palms,127shrubs,18ground-covers, four vines, and three grasses.Despite the linear restriction ofthe garden, plant arrangement wasbased on five design principles, in-cluding color, line, form, texture,and scale. To achieve this, a masterspreadsheet was developed to catego-rizeleafpersistence,maturewidthandheight,floweringtime,andflowerandfoliagecolor.Acomputer-aided draft-ing program (AutoCad 2002, version3.3; Autodesk, San Rafael, CA) wasused to create the base sheet, sche-matic, and master plans. Rhythm,unity, and structure were achievedthrough alternation of large and smalltrees with deciduous and evergreenleaf persistence. A vertical transitionwas created by grouping and replicat-ing trees, vine structures, and palms.Plants of similar color, form, andtexture were placed equidistant fromthe center of each tree grouping,creating not only repetition but bal-ance through symmetry. Shrubs,groundcovers,andgrasseswereplacedbetween all trees and palms to createcolor, scale, and texture.Units