I found some of the chicken grit at the Linton Feed & Seed - not too far out of the way. They just happened to be all out of the big bags, but had about 10 lbs left in the by the pound bin, which I think was just about enough? I raked it into the area where I haven't yet planted, and around the semps themselves, then put another layer around them, better?
I tried to press it up under the leaves as much as I could without disrupting the plants. I'm guessing now that maybe they should be planted a little above the soil, then backfilled with this stuff in the future?