Kohleria villosa 
Kohleria warszewiczii 
Korean Goldenbell Tree 
Korean perilla 
Labrador Indian paintbrush 
Lachnostachys verbascifolia 
Lallemantia peltata 
Lambs-ear 
Lamium bifidum 
Lamium orientale 
Lance Selfheal 
Large Beardtongue 
Large self-heal 
Large-flowered calamint 
Large-flowered hemp-nettle 
Laurel clock vine 
Lavandula coronopifolia 
Lavandula subnuda 
Lavender bladderwort 
Lavender Broomrape 
Lavendula pedunculata 
Leafless-stemmed Globularia 
Legazpia polygonoides 
Lemon balm