Thanks Mr Ants, most places I’ve read suggest a cold stratification too.
I have grown A. pavia from seeds the past two seasons and have tried various approaches.
Dirr says that A. pavia and A.parviflora need no stratification to germinate. I have had success with no cold stratification but then the plants are WAY out of phase with nature and that causes a new set of problems come spring! On the other extreme I have stored seeds in a refrigerator (never below 32F) all winter and had 0% germination in the spring.
I’m going to try something a little different this time. I put my buckeyes (A. pavia, A parviflora, A. trubinata) in some rubbermaids and set them outside. It’s already pretty chilly here. The plan is to leave them out there until probably mid November. Then bring them inside and raise them inside until spring. I’ve never seen a buckeye seed survive a Michigan winter outside, it’s just too cold. Hence I think I need to bring them in at some point.