Monarch butterfly laying an egg on an emergent common milkweed leaf on Sunday in Green-Wood. This little plant is an outlier from the patch here, in danger of being mown or “weeded,” alas.
I also watched her deposit eggs on two much taller, already flowering, plants that were part of the official patch.
Closer up, you can see that the tiny eggs are grooved.
Do they ever lay more than one egg per plant? How many eggs per female? Is there anything stopping other Monarchs from laying on the same plant?
Backyard and Beyond 
Those last are all intriguing questions. I’m asking anyone here with observational insight to respond. My interest comes from a fairly large planting in Florida some time ago. I only saw moderte incrwe in Monarch population.
Hi Matthew,
Nice find. I have a chapter on milkweed in my new Summer Wildflowers book. Monarchs will generally lay only one egg on a plant, the exception being on small, emerging plants – the reason for that is unknown. If a subsequent monarch were to lay an egg on a plant that already has one, the earlier hatching caterpillar would consume the later hatching competitor. There is a wonderful book by Anurag Agrawal called Monarchs and Milkweed that goes into great detail about the relationship between the two species.
Carol
Very nice! This milkweed likes to travel underground. I planted one little seedling in a flower patch last year. It didn’t look like much all season long, but come spring it turned out, it has been awfully busy underground. Popping up all over from underground rhizomes even over two yards away 🙂