If they're really black eyed susans, you can plant a few and pot a few and take the mature seed heads and spread them where you want that English garden look.
I did that with no plants, just the seed heads of susans and perennial ageratum. They both bloom at the same time in later summer and for a long time and the color combo has been beautiful.

Chop down the spent plants after the first frost and they will return next spring from the roots and from the dropped seeds the goldfinches miss.
I didn't do the full sun but a north location bed that gets some nice am sun and some hard afternoon sun.
Both are spreaders mostly by seed so give your black eyed susans lots of space or a bed of their own.

I think you did the right thing. If you were to put them in full sun right now you'd probably lose them. Keep your potted seedlings in morning sun and then plant them out in early to mid October. Soon you'll be the one giving them away!

I planted all my remaining pot stock (assorted perennials) today...as we have a full week of scheduled rain and temps mainly in 70s (wow..where did those 90s go?). I'm prepared to water as needed if rain stops and/or temps rise.

Dear dottie in charlotte, puppyscruff and dbarron,
Many thanks for you kind and very helpful replies to my question.
In the pot they stay; until probably three weeks from now.
Then, into the ground they go!
Have already installed new water lines from the drip irrigation system to the planting site.
And Miss Dottie, I'll be spreading those seeds!

Don't go overboard with the watering. These are hardy once they're established. They don't like constant wet foliage that comes from overhead sprinkling.
I got my seeds from plants in an elevated median of our roadway. It got rain or it got nothing and they thrived once established.

Thanks again!
And, Ditto on the not over watering advice.
With the cool forecast for this weekend, I'm tempted to do the deed!