Sage

Salvia 

Sanguinaria

Sanguisorba

Schizachyrium

Sea Holly 

Sea Thrift

Sedum

Sesleria

Shasta Daisy 

Showy Milkweed

Siberian Iris 

Siberian Larkspur

Silene

Smooth Blue Aster

Sneezeweed

Snowdrop

Solidago

Solomon’s Seal

Solomon's Plume

Speedwell

Sporobolus

Stachys

Stokesia

Stoke's Aster

Stonecrop

Swamp Milkweed

Switch Grass

Symphyotrichum

Honeysong Purple: © Wit’s End Gardens
Little Miss Sunshine: Walters Gardens
Caradonna: Averater, CC3, via Wikimedia Commons
autumnalis: © Wit’s End Gardens