I have grown coreopsis before, starting it indoors on the theory that it was a hot weather plant that needed heat to get a good start.
I quite enjoyed the dwarf mix I got a year or two ago, but they started blooming late, and the plants were very leggy… so I decided I probably didn’t have enough sun, and wouldn’t grow them this year.
I mentioned elsewhere that I tried Schizanthus (Poor Man’s Orchid) this year, direct sown into large pots.
Mid-spring, I noticed that some of the “Schizanthus” clumps were not like the others. In fact, they looked suspiciously like coreopsis!

I had reused the soil, and apparently my extra layer of coir/perlite/vermiculite to guarantee a clean base was just thick enough to make the coreopsis happy.
The result is a lovely airy cloud of color.
This is definitely the way to do coreopsis!

I’ll be trying to deliberately reproduce this serendipity next winter.
Wish me luck!