Leopard's-Bane 
Lesser burdock 
Lessingia leptoclada 
Lessingianthus bardanoides 
Leucophyta 
Lilac Tasselflower 
Lindley's Aster 
Linochilus eriophorus 
Lion's-foot Rattlesnake-root 
Little pickles 
Lobelia borneensis 
Lobelia erlangeriana 
Lobelia giberroa 
Lobelia minutula 
Lobelia pedunculata 
Lomelosia micrantha 
Lomelosia porphyroneura 
Long-Beaked Salsify 
Loricaria complanata 
Loricaria thuyoides 
Luina hypoleuca 
Lychnophora salicifolia 
Lysipomia brachysiphonia 
Madagascar ragwort