300+ Peppermint Seeds- Heirloom Herb- by Ohio Heirloom Seeds Shipping is free on all additional seed packages purchased with this item, all varieties, any quantity. Pay only $1.69 shipping per Order! Grown in 2018 for the 2019 season To sow the seeds indoors, place the seeds on top of the medium in your seed flat. Do not cover the seeds; they need light to germinate. They should sprout within 14 to 21 days at room temperature or slightly warmer (68 to 75F). Transplant into the garden or container when they have at least 2 sets of true leaves.