| Scientific Name | Common Name(s) | Life History | Growth Form | |
|---|---|---|---|---|
|
Salvia verbenaca | vervain sage, wild clary | Perennial | forb |
|
Salvia x sylvestris 'Mainacht' MAY NIGHT | May Night sage, meadow sage, violet sage, wood sage, woodland sage, balkan clary | Perennial | forb |
|
Sambucus tigranii | red elder, elderberry, Tigran's elder, Caucasian elder | Perennial | shrub |
| Saponaria ocymoides | rock soapwort, tumbling-Ted | Perennial | forb | |
|
Scabiosa atropurpurea | Pincushion flower, mourningbride, sweet scabious, mournful-widow, pincushions, purple pincushion, Pincushion plant | Perennial | forb |
|
Schinus molle | australian pepper , California pepper-tree, molle, pepper tree, Peruvian mastic-tree, Peruvian pepper-tree, pirul, Peruvian-mastictree, aguaribai (Spanish), pimientero falso (Spanish), rosépeppar (Swedish) | Perennial | tree |
|
Schinus polygama | Hardee peppertree, Chilean peppertree | Perennial | shrub |
|
Schinus terebinthifolia | Brazilian pepper tree, Christmas berry, Florida holly | Perennial | shrub |
|
Scilla siberica | Siberian Squill | Perennial | forb |
|
Scolymus hispanicus | goldenthistle, Spanish oysterplant, Spanish salsify | Biennial | forb |
|
Searsia lancea | African sumac, karee, willow rhus | Perennial | tree |
| Securigera varia | Purple crownvetch, trailing crownvetch | Perennial | forb | |
|
Senecio angustifolius | Bitter Bush | Perennial | shrub |
| Senecio elegans | redpurple ragwort, purple ragwort, wild cineraria | Annual | forb | |
|
Senecio linearifolius | fireweed groundsel, linear-leaved Australian fireweed | Perennial | shrub |
| Senecio quadridentatus | cotton burnweed, cottonweed | Annual | forb | |
|
Senna artemisioides | Silver Senna | Perennial | shrub |
|
Senna didymobotrya | African senna, candelabra-tree, peanut-butter cassia | Perennial | shrub |
|
Senna multiglandulosa | glandular senna, buttercup bush | Perennial | shrub |
|
Solanum aviculare | New Zealand nightshade, kangaroo-apple, nightshade | Perennial | shrub |
|
Solanum carolinense | Carolina horsenettle , ball nightshade, ball-nettle, horse-nettle | Perennial | forb |
|
Sorbus alnifolia | Korean Mountain Ash | Perennial | tree |
| Sphaeralcea munroana | orange globe mallow, Munro's globe mallow, white-stem globe mallow, desert mallow | Perennial | forb | |
|
Sphaerophysa salsula | Alkali swainsonpea, Austrian peaweed, red bladder-vetch | Perennial | forb |
|
Spiraea japonica | Japanese spirea, Japanese meadowsweet, maybush | Perennial | shrub |