If I don't find any, is it alright to cut back both plants before the seed pods mature? I really don't want seedlings all over the place. I have acres of woods and pasture where they are welcome but not in my perennial garden.

I haven't seen any Monarchs yet, but when I do see a female ovipositing I try to collect the eggs as soon as possible, because chances are the numerous predators in the garden will make a meal of them - they might not last a day.

If the egg survives and hatches, the caterpillars are tiny at first and not always easy to find. They are also susceptible to predation and may not make it to the larger caterpillar stages. Because of the predators, I take many eggs and a few caterpillars inside to raise.

You can cut down your milkweed if there are no eggs or caterpillars on them. About a month ago, I cut back (by half or so) a lot of my the common milkweed and pinched the tropical, so they will send up fresh shoots. These shoots are very desirable to the Monarch females, because the foliage quality is superior and they're easier for small caterpillars to eat.

If you decide to let some pods go to seed, you could collect some and scatter the seed yourself in your pasture before they reseed in your garden. Win-win. (I do this a lot in wild areas.)