Mentha longifolia, Horse Mint seeds
Mentha longifolia seeds, Horse Mint
Mentha longifolia is also known as Horse Mint. The plant is native to Europe but also to regions in Africa and Asia that are not belonging to the tropics. The Horse Mint is a perennial, herbaceous plant and is one of the bigger mints. It can reach heights between 0,5 m and 1 m. It has the typical peppermint smell, but in this species the mint odor is sometimes recognized as unpleasant. The leaves of the Horse Mint are lanceolate and strongly pubescent. The leaves get 9 cm long. That is quite long for a mint species. Due to that the mint was named "longifolia" meaning long leaf. The older leaves are grayish green; the young leaves are fresh light green. The leaf margin is clearly dentate. The flowers are zygomorphic and are clustered in inflorescences at the end of the shoot. The shoot ends up in several inflorescences. The flowers are slightly rose or white and just 5 mm long.
The flowering period starts in July and ends in September. The root is a rhizome. With that rhizome the Horse mint is able to spread itself via runners. Mentha longifolia is used in folk medicine since long time. A tea that is made from the leaves is used against cough and stomach ache and other intestinal problems. The Horse mint also helps against headache. For the tea it is best to harvest the leaves before the plant starts flowering. Mentha longifolia can also help against insect stings. A compress with mint on the insect sting mitigates the pain and the itching and cools from outside. Eaten raw the leaves of the Horse mint do not have a good taste.
The seeds of Mentha longifolia need light to germinate. Because of that the seeds should be only pressed slightly into the substrate. It is best to sow the seeds directly outside in autumn or winter. That raises the germination success in spring. At a temperature of just 15°C the seeds start to germinate after 3 to 6 weeks in the moist substrate. The Horse mint needs a soil that is rich in nitrogen. Adult plants also prefer constantly moist soil and half shaded places. They do not tolerate direct sun.