I’m tearing out all of my hollyhocks this week. I give up. They’ve been infested by hollyhock weevils. The critters started showing up last year, and despite my attempt to discourage them by removing all foliage at the end of the season, here they are. They appear in pairs, sometimes mating, as seen above, or because the male stays very close to the female to make sure another male doesn’t take over. The female is using her long snout to drill into the developing seeds to deposit eggs.
Even before you see this kind of activity on developing flower heads before they open, there is damage on the leaves as the adults feed.
The plants still flower OK, but the plants are not healthy and they’re just serving as nurseries for more and more and more weevils.
Here’s part of a dried seed capsule covering with evidence of a weevil egg hole
And a closer look at seeds where eggs were deposited.
The larvae develop in the seed, destroying it, with young weevils waiting to emerge in the spring spring. If you want to save seed for future years, examine every single seed and only keep ones without weevil drilling.
There are also some chemicals available, but since I don’t use chemicals, I will rely on keeping hollyhocks out of my landscape for a few years so there’s nothing for them to eat or use for reproduction.