Boerhavia elegans 
Boerhavia repens 
Bolanthus filicaulis 
Bolanthus hirsutus 
Bolivian torch cactus 
Boreal chickweed 
Boreal starwort 
Bosea yervamora 
Bougainvillea × buttiana 
Branched Pencil Cholla 
Brandegee's Hedgehog Cactus 
Bridal rainbow 
Broad-leaved dock 
Broadleaf Knotweed 
Brotero's Pink 
Buckhorn cholla 
Buckwheat 
Bufonia multiceps 
Bufonia ramonensis 
Bulgarian statice 
Bunny Ears 
Burbidge's Pitcher-Plant 
Burrowing Four-o’Clock 
Bushy knotweed