I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
Those plants are not great repeat bloomers in your climate. They can take a little fertilizer such as Miracle Gro at the low "constant feed" rate every once in a while. They need sun in order to bloom well so yours are in a good spot. The setback from worms probably cost you a lot of bloom time this year. Other than preventing worm defoliation and a light feeding I can't think of anything else you can do.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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