old pennyroyal bed

yall, this past spring i pulled up all the pennyroyal in my stock tank, leaving a well-pruned weigela and a bunch of fresh zinnia seeds, which in spite of the addition of 10 bags of miracle grow potting soil turned out one whole plant. i would like to try some greens this year, but im cconcerned about residual poisons possibly left in the old soil by the pennyroyal. i dont want to lose my liver but i dont want to lose that vegetable space, either. can anybody give me some advice? i cant find not one word on this anywhere. thank you.

Plants do not leave poisons behind that will be taken up by your next plant. you can happily eat a lettuce leaf that grew right next to a foxglove or a daffodil with no worries both of which are much more poisonous than penny-royal which was and in some places still is a common food flavouring.

So in short you have nothing to worry about with whatever you plant there.

skandi, thank you SO MUCH.

The essential oil, pulegone, from pennyroyal has been demonstrated to act as a germination inhibitor and based on your seeding experiment there seem to be residuals that have not cleared the soil yet.  I couldn't find anything indicating how long it will take for the soil to clear that inhibiting compound, but rather than wait perhaps start some seeds in pots and then transplant them in.  If you happen to take some notes on how long before seeds start to germinate in the soil or if there are any issues with transplanting into the bed and share those here I'm sure many of us would be very interested in your findings Coby!
abstract discussing essential oil testing for germination inhibition

greg, thank you muchies, and ill be glad to report back.