Asclepias curassavica


Tropical milkweed (Asclepias curassavica) is probably the most talked about plant in many years if not the most talked about plant ever. Other common names include bloodflower or blood flower, cotton bush, hierba de la cucaracha, Mexican butterfly weed, redhead, scarlet milkweed, and wild ipecacuanha. I have also seen the common name butterfly milkweed applied to it, a name that was used for years for Asclepias tuberosa. Most say it is native to the American tropics and has a pantropical distribution as an introduced species. It has been in Louisiana for a long time with an herbarium collection on Nov 10, 1887 from New Orleans by Joor and one from along the River’s edge in Pilottown in Plaquemines Parish by Joseph Ewan Nov 22-23, 1947. The 1887 record is before we knew that monarchs migrated and the 1947 was before we knew where they migrated to in Mexico (see next paragraph). My understanding of the monarch life cycle is that in early spring, the monarchs that overwintered in Mexico and are about six months old, fly north and lay eggs on milkweeds in south Louisiana, Texas, etc. And then those six month old monarchs die but their off spring eclose out of a chrysalis and fly north and reproduce and die after living for about two weeks. These monarchs oversummer (a new word) in the northern United States and even into Canada. This repeats during the summer but toward the end of August, the group of monarchs produced then fly south into Mexico and overwinter. Then the next spring the six month old monarchs fly north into south Louisiana and Texas to start the cycle again. I have jokingly said that if you are going to be reincarnated as a monarch, ask to be in the late August group so you can live for six months instead of two weeks and get to travel a lot. So, at Allen Acres, we focus on having milkweed ready in March-April only. We rarely see a monarch except March-April and then again October-November.