Reader question… “Last year I planted a few peppermint seeds. The plants grew well but don’t smell as pepperminty as I thought they would. I was telling this to my neighbor and she says I couldn’t have planted peppermint seeds because peppermint is sterile and doesn’t produce seeds. She says I planted some other kind of mint but not peppermint. The thing is, I saved the seed packet and it IS labeled as peppermint. I remember reading in one of your posts (don’t remember which one) that you grow peppermint so I thought you might know which of us is right.” –Izza W.
In a way, you both are…
True peppermint (Mentha x piperita) is a hybrid… a cross between spearmint and watermint… and true peppermint is sterile, so it does not produce seeds. Like other mints, true peppermint spreads through its underground rhizomes. New plants can also be grown easily from division or cuttings.
The seeds commonly sold as peppermint are actually a form of spearmint. I would guess that this is what you planted… and you’re right, this mint does not smell like the true peppermint.
Peppermint seedlings (see the red stems)
True peppermint also looks very different from the so-called peppermint grown from seeds. The stems are smooth, square and dark with a touch of red, and the leaves are also smoother and a darker green and have reddish veins.
I actually acquired my first peppermint plant by accident. I had purchased several other herbs from a local nursery, and as I was planting these herbs in the garden, I found a tiny peppermint plant in one of the pots. I have always wondered where it came from because that particular nursery did not (and does not) sell true peppermint. I have never seen true peppermint for sale, although I am sure some nurseries must sell it. In our area, the plants that are labeled peppermint are obviously the “peppermint” that is grown from seeds.