How to tell difference between pennyroyal and mint

[puzzlejunky]

When my elderly neighbor passed away, the new buyers of the home gave me what they thought were peppermint plants growing in their lawn. I replanted them in my lawn, and they're pretty invasive. As the original planter has passed away..I have no idea if they truly are peppermint.

They grow pretty close to my lemon balm and I don't want them to cross-pollinate, so I yank them out of the ground before they flower.

I was thinking of potting them up and moving them elsewhere and growing them for tea. However , if they are pennyroyal I don't want to serve them to anyone pregnant (pennyroyal is an abortificant)

How do you tell the difference BEFORE they flower?

[rainbowgardener]

Well, pennyroyal and peppermint are both mint (even the lemon balm is in the mint family). But distinguishing pennyroyal from peppermint is not hard. Peppermint is a classic mint, with strong stems that grow vertically, long oval leaves pointed at both ends, and heavily crinkled:


https://www.naturalremedies.org/images/peppermint-1.jpg

There are a lot of varieties of pennyroyal, but many of them are more prostrate, creeping plant, like a ground cover, with smaller rounder leaves:


https://innocentprimate.files.wordpress ... g_4570.jpg

More rarely there is an erect version of pennyroyal, but it is still smaller in leaf and stem:


https://www.ramshillfarm.com/Farm/Plants ... Royal1.jpg

[puzzlejunky]

Thanks Rainbow! I think it is indeed peppermint!

[benali]

I try a simple taste test. In my experience, peppermint is readily distinguishable from more "spearmint-like" mints such as pennyroyal. Peppermint comes on direct and strong, pennyroyal is more a spearmint flavor. Cheers.