That's why I like the theory that it was just used ta numb her.

[ he hums thoughtfully ]

Okay, lets play the devil's advocate for a moment here. What if the lemons were ta mask the fruit -- although, the root was found with it, wasn't it? wouldn't that be obvious? - anyway, lets say the lemons were ta mask the fruit an' she invited someone ta dine with her intendin' ta kill them. She'd eat a little bit, get a little high, but they'd eat a lot an' die. Only, they figured it out an' then they killed her.

It's not the theory I subscribe ta, but it could explain the lemons.