Two of the wildflower species in the mix have really taken off and gotten tall where I planted them. (Some others blew elsewhere in the yard and got a foothold there, I believe.) Thanks to plumtreeblossom’s research, I know that they are Cosmos and Coreopsis, and they’ve both gotten over a foot tall — the Cosmos well over.
Last night I saw my first blooms in the patch I’d deliberately planted, but they were something I hadn’t even noticed among the Cosmos and Coreopsis before — little white flowers maybe a centimeter and a half across. This morning one of the Coreopsis buds had blossomed into a lovely orange-yellow flower. Yay!