Gorgeous Monarch Butterflies and Caterpillars Brighten the Garden this Week

My native Coral Honeysuckle attracted this beautiful, fresh-looking Monarch Butterfly this week. Temperatures up here in northern New Hampshire will soon be too cold for Monarchs to continue to lay eggs and for new caterpillars to emerge, so this particular butterfly will likely be migrating 3000 miles to Mexico.

Amazingly, nanotags tiny enough to be attached to migrating Monarchs are sending signals picked up by towers, letting us know where they go and how fast they travel. At left is a Februaury, 2023 picture from Piedra Herrada, Valle de Bravo, one of a number of Mexican sanctuaries for Monarchs, whose populations are in serious decline. Data from the nanotags will help scientists identify areas to protect for them. Already some tagged in New Hampshire have been have been detected in the Blue Ridge Mountains some 520 miles south. If all goes well some of these migrants will return here in the spring to mate and lay eggs and begin the cycle again.

Photo by: Charles J Sharp (CC BY-SA 4.0)

In another part of the garden this week, a Monarch in the caterpillar stage of its lifecycle shares a Butterfly Milkweed seed pod with a Swamp Milkweed Leaf Beetle. A prior generation of a Monarch butterfly must have laid its eggs on this plant, the only one in the garden the caterpillar can eat.

I have only seen these caterpillars eat milkweed leaves, and was transfixed by the voracious way it ate the seed pod – kind of like it was eating corn on the cob. It spent 3 or 4 days on the plant, and is gone now, to spin its chrysalis and pupate into a butterfly if all goes well. I’ll be on the lookout for more butterflies emerging in the next few weeks and foraging a bit in the garden before heading south. We gardeners can help monarchs by planting milkweed, which is essential for them, and by avoiding pesticides.