Are they bedding plants? Do you dead head them to get more flowers?
Garden Flower ,Portulaca
I can't imagine dead-heading individual flowers; they are so small. But every couple of weeks, I do remove spent stems down to the new side-shoot. Save some seed for next year or let it self-sow before the end of the season. I'm hoping another poster will chime in and say they don't dead-head and their plants bloom happily all summer. Or do your own experiment and dead-head every other plant. Then you can reply to your own post with the answer.