Aquilegia blooms come in many colors,and when you put 2 or more different colored ones together, they will cross pollinate and have a bunch of mixed offspring,some of those being quite showy.ASAP concerning the Cardamine bomb that's about to explode.Too much of a bad thing isn't good.

Don't be afraid, let them go to seed. You will have them spread nicely among the other flowers in the coming years. Sometimes there will be more of them, the colours will be different, another year they will almost disappear. But they will never try to take over and smother other plants in the bed. This I know from experience.

Hibiscus trionum, a flowery weed or weedy flower depending on your point of view.

I'm kind of hoping someone on this thread still has their notifications on - otherwise I'll start a new post. But you all knew your weeds - so I'm hoping you won't mind one more. I initially thought this was a mosquito plant -- it looked very similar to one that I planted about 5+ years ago that did not come back last year, so I was surprised to see this emergence - and several others - scattered around my flower beds. However, doing a search to confirm it was a mosquito plant (citronella) all mentioned that it has a nice smell when you crush the leaves. These plants/weeds have no such smell - and so far have no flowers - leading me to presume this is a weed. But it does have a nice tidy habit and is quite pretty - so I'm hoping someone tells me it will produce flowers - I'm ok with pretty weeds, as long as it produces flowers for the bees. :-) Thank you!