Here's a shot of some of the smaller ones showing their red stems:

Pokeweed?

Talinum paniculatum if I'm seeing a little sprig of pink buds at the top?

The leaves seem too round for pokeweed. Also, don't believe their stems usually turn red this young. We actually have a young pokeweed nearby to compare with and it looks like this:

purpleinopp, Yes, it does appear to be forming buds and some good matches on photo search, so T. paniculatum looks like a pretty good fit. Never would have come up with that.

Thanks to all for the suggestions!

This plant has opposite leaves; pokeweed's are alternate.

Glad to learn it's probably the 'Limón' Jewels of Opar (Talinum paniculatum) cultivar developed for that chartreuse leaf color. I had repotted them in a mix of native soil and first thought they might be going chlorotic in our moderately alkaline clay.

Here is a link that might be useful: Limón talinum is jewel for gardens

This post was edited by bostedo on Fri, Oct 11, 13 at 13:29