Yes.

welcome to GoY
as Owd says yes remove spent flowers. this is true for most flowering plants which is why deadheading is a regular past time for us gardeners!

The gardener in summer: a sunrise....sweat pants!...the cuppa!...and the thumb and forefinger....AAhh, now the smile! :D

Thanks everyone. I assumed so, but I remember when I was young (a long time ago - lol!) my mom sent me out in the fall to pick the seeds to save for the following spring, so I wasn't sure if she had deadheaded during the earlier part of the season or not. I remember this vividly as I went to pick one and instead of a seed it was a brown spider all curled up - scared the crap outta me!!! I guess if I want to have some for next year, I'll just let them go to seed later in the season but I'll be careful to watch for spiders! Have a wonderful summer! It seems it's finally arrived here in Nova Scotia:)

In theory, deadheading helps, but in practice, I've never bothered to deadhead those that pop up in the garden from previous year's seeds, and they're usually still flowering when the first frost arrives in November, so I'm not certain it makes much difference.

Yes, and succession planting. Start up some new plants now to replace the other plants when they fizzle out or start looking anemic. After a couple weeks, start up new plants again to take you into frost. Get rid of the ugly plants.

Bad poetry aside, I usually actually let them set seed all they want, so I get a good crop of seedlings when they come up again in fall. In my climate, they grow over the fall and early winter, and bloom for a few months starting in late January, then die in the summer. I usually reserve those half-hour interludes of peace for gentle maintenance of roses, daisies, snapdragons, etc.