Huh, I read the Abstract and then the nat geo article. Based on what nat geo said, it sounds like she checked each plant each week for 28 days. I wonder how long they keep that information, since it says bees can only keep a discovery for a few days.

If I were this researcher, I'd consider testing 2 plants (or three if she had an extra 28) every single day. Each day is a new set of plants that had stopped curling up, and checking to see if they "remember" that they don't need to curl up. Idk, I don't have full access to the paper, so maybe the researcher did do that, or plans to.