Sagina procumbens
Procumbent Pearlwort
Salpichroa origanifolia
Cock's-eggs
Salvia microphylla
Blackcurrant Sage
Salvia officinalis
Sage
Salvia pratensis
Meadow Clary
Salvia verbenaca
Wild Clary
Samolus valerandi
Brookweed
Saponaria officinalis
Soapwort
Saxifraga cespitosa
Tufted Saxifrage
Saxifraga granulata
Meadow Saxifrage
Saxifraga hypnoides
Mossy Saxifrage
Saxifraga oppositifolia
Purple Saxifrage
Saxifraga spathularis
St Patrick's-cabbage
Saxifraga tridactylites
Rue-leaved Saxifrage
Scleranthus annuus
Annual Knawel
Scorzoneroides autumnalis
Autumn Hawkbit
Scrophularia auriculata
Water Figwort
Scrophularia nodosa
Common Figwort
Scutellaria galericulata
Skullcap
Scutellaria minor
Lesser Skullcap
Senecio inaequidens
Narrow-leaved Ragwort
Senecio viscosus
Sticky Groundsel
Senecio vulgaris
Groundsel
Serratula tinctoria
Saw-wort
Sherardia arvensis
Field Madder
Silene acaulis
Moss Campion
Silene conica
Sand Catchfly
Silene dioica
Red Campion
Silene flos-cuculi
Ragged-Robin
Silene gallica
Small-flowered Catchfly
Silene latifolia
White Campion
Silene noctiflora
Night-flowering Catchfly
Silene nutans
Nottingham Catchfly
Silene uniflora
Sea Campion
Silene viscaria
Sticky Catchfly
Silene vulgaris
Bladder Campion
Sinapis arvensis
Charlock
Solanum chenopodioides
Tall Nightshade
Solanum dulcamara
Bittersweet
Solanum nigrum
Black Nightshade
Sonchus arvensis
Perennial Sow-thistle
Sonchus asper
Prickly Sow-thistle
Spergularia rubra
Sand Spurrey
Spergularia rupicola
Rock Sea-spurrey
Stachys alpina
Limestone Woundwort
Stachys arvensis
Field Woundwort
Stachys byzantina
Lamb's-ear
Stachys germanica
Downy Woundwort
Stachys palustris
Marsh Woundwort
Stellaria alsine
Bog Stitchwort
Stellaria aquatica
Water Chickweed
Stellaria graminea
Lesser Stitchwort
Stellaria holostea
Greater Stitchwort
Stellaria neglecta
Greater Chickweed
Succisa pratensis
Devil's-bit Scabious
Symphytum officinale
Common Comfrey
Symphytum orientale
White Comfrey
Symphytum x uplandicum
Russian Comfrey
Taraxacum falcatum
Dandelion
Taraxacum 'iscanum'
Taraxacum palustre
Tellima grandiflora
Fringecups
Torenia crustacea
Malaysian False Pimpernel
Tragopogon porrifolius
Salsify
Trifolium arvense
Hare's-foot Clover
Trifolium hybridum
Alsike Clover
Trifolium medium
Zigzag Clover
Trifolium micranthum
Slender Trefoil
Trifolium scabrum
Rough Clover
Tuberaria guttata
Spotted Rock-rose