South African Acanthus 'Southern Belle' Rose Mallow
Southern Blue Flag 'Purple Fan' 'Southern Comfort' Alumroot: Heuchera
Southern Lady Fern (spp.) Southern Lady Fern 'Veronica-Cristata'
Southern Maidenhair Fern Southern Red Trillium
Southern Star Southern Sundrops
Southern Wood Fern Southern Wood Fern: normalis
Southern Woodland Penstemon Sowbread
'Space Wars' Daylily Spanglegrass
Spanglegrass River Oats Spanish Bayonet (spp.)
Spanish Bayonet 'Marginata' Spanish Bayonet Variegated
Spanish Bluebells (spp.) Spanish Bluebells 'White City'
Spanish Broom Spanish Chamomile
Spanish Dagger (spp.) Spanish Dagger 'Marginata'
Spanish Dagger Variegated Spanish Flag (spp.)
Spanish Flag 'Citronella' Spanish Iris (spp.)
Spanish Lavender 'Silver Anouk' Spanish Moss
Spanish Needle 'Golden Eye' Spanish Needle 'Marietta Gold Spark'
Spanish Needle 'Summerlovers Biden 1850' Spanish Reed Grass (spp.)
Spanish Reed Grass 'Picta' Spanish Reed Grass Variegated
Spanish Shawl Spanish Thyme (spp.)
Spanish Yucca 'Sparkle Devine' Cardinal Flower
'Sparkler' African Daisy: Osteospermum Sparkler Sedge 'Sparkler'
'Sparkler' Sparkler Sedge 'Sparkling Burgundy' Pineapple Lily
'Sparkling Cheryl' Florist's Chrysanthemum Spatterdock
Spear Grass Spear Grass: colensoi
Spear Grass: tenuissima Spearleaf Stonecrop
Spearmint 'Kentucky Colonel' Spearwood Bush
Spearwort, Greater Creeping Spearwort, Lesser
'Speciosa (Firetail)' Knotweed: amplexicaule 'Speciosum' Sacred Lotus
Speckled Wood Lily Speedwell, Alpine Groundcover
Speedwell, Alpine White Speedwell, Austrician 'Trehane'
Speedwell, Cascade Speedwell, Creeping 'Sunshine'
Speedwell, Gentian (spp.) Speedwell, Gentian 'Barbara Sherwood'
Speedwell, Gentian Variegated Speedwell, Harebell 'Aztec Gold'
Speedwell, Harebell 'Blue Sheen' Speedwell, Hungarian (spp.)
Speedwell, Hybrid 'Giles Van Hees' Speedwell, Hybrid 'Miffy Brute'
Speedwell, Hybrid 'New Century' Speedwell, Long-Leaf (spp.)
Speedwell, Long-Leaf 'Foersters Blue' Speedwell, Long-Leaf 'Sunny Border Blue'
Speedwell, Montana 'Corinne Tremaine' Speedwell, Prostrate 'Aztec Gold'
Speedwell, Prostrate 'Blue Sheen' Speedwell, Saw Leaved (spp.)
Speedwell, Silver Speedwell, Spike (spp.)
Speedwell, Spike 'Blue Bouquet' Speedwell, Spike Dwarf
Speedwell, Spike 'Icicle' Speedwell, Woolly
Speedwell, Wooly Speedwell: austriaca, Saw Leaved 'Trehane'
'Spendreit' Guzmania