Acanthus balcanicus 
Acanthus hirsutus 
Acanthus syriacus 
Aeschynanthus tricolor 
African violet 
Agastache aurantiaca 
Allegheny Monkeyflower 
Alpine butterwort 
Alpine Cancer-root 
Alpine Toadflax 
American alpine speedwell 
American Beautyberry 
American Cancer-root 
American Germander 
American Lopseed 
American Speedwell 
American water horehound 
Amethyst broomrape 
Anarrhinum forskahlii 
Anemopaegma arvense 
Anise Hyssop 
Anisomeles indica 
Anisosepalum humbertii 
Anisotes madagascariensis