Sedum confusum Sedum dasyphyllum
Sedum divergens Sedum lanceolatum
Sedum morganianum Sedum praealtum
Sedum rubrotinctum Sedum spathulifolium
Sedum spathulifolium 'Cape Blanco' Sedum ternatum
Sedum ternatum 'Shale Barrnes' Sedum tetratinum
Senna covesii Senna marilandica
Senna polyphylla Sequoia sempervirens
Sequoia sempervirens 'Filoli' Sequoia sempervirens 'Prostrata'
Sequoia sempervirens 'Soquel' Sequoiadendron giganteum
Sequoiadendron giganteum 'Pendula' Serenoa repens
Seriphidium canum Seriphidium tripartitum
Shepherdia argentea Shepherdia canadensis
Shepherdia rotundifolia Shortia galacifolia
Sidalcea x 'Party Girl' Sidalcea malviflora 'Elsie Heugh'
Sidalcea malviflora 'Little Princess' Silene polypetala
Silene virginica Silphium perfoliatum
Simarouba glauca Simmondsia chinensis
Sisyrinchium angustifolium Sisyrinchium angustifolium 'Lucerne'
Sisyrinchium angustifolium 'Quaint & Queer' Sisyrinchium bellum
Sisyrinchium bellum 'Rocky Point' Sisyrinchium californicum
Smilax hispida Smilax rotundifolia
Solandra maxima Solanum carolinense
Solidago canadensis Solidago canadensis 'Crown of Rays'
Solidago rigida Solidago rugosa 'Fireworks'
Solidago spathulata 'Golden Fleece' Sophora affinis
Sophora secundiflora Sophora tomentosa
Sorbus americana Sorghastrum nutans 'Indian Steel'
Sparganium androcladum Spartina alternifolia
Spartina bakeri Sphaeralcea ambigua
Sphaeralcea munroana Spigelia marilandica
Spiraea douglasii Spiraea splendens
Sporobolus capillaris Sporobolus heterolepis
Sprekelia formosissima 'Superba' Stachys albens
Stachys palustris Stenocereus alamosensis
Stenocereus dumortieri Stenocereus eruca
Stenocereus gummosus Stenocereus montanus
Stenocereus thurberi Stewartia malacodendron
Stewartia ovata Stipa tenuissima
Stokesia laevis Stokesia laevis 'Blue Danube'
Stokesia laevis 'Honeysong Purple' Stokesia laevis 'Klaus Jelitto'
Stokesia laevis 'Mary Gregory' Stokesia laevis 'Omega Skyrocket'
Stokesia laevis 'Purple Parasols' Stokesia laevis 'Silver Moon'
Stylophorum diphyllum Styrax americanum
Suriana maritima Swietenia macrophylla
Swietenia mahagoni Swietenia mahagoni x macrophylla
Symphoricarpos microphyllus