Mesosphaerum suaveolens aka Pignut

Mesosphaerum suaveolens is in Lamiaceae, the mint family. It is native from Mexico through the tropics of America. Some sources use the name Hyptis suaveolens. It has spread through the world's tropics and subtropics. Kew places it in a tropical biome with dry seasons. People gather wild plants for food and folk medicine. Growers also raise it for seed in Mexico and India.

This upright plant has a coarse form and many branches. Kew lists it as an annual, living for one year. Useful Tropical Plants also notes plants that live for several years. Their stems grow woody and last from season to season. That source gives a height of about 6.6 feet [2 metres]. Some reach 8.2 feet [2.5 metres], though most stay much shorter. Its form can thus range from an annual herb to a shrub.

Plants can start to bloom at eight to twelve weeks old. They may keep blooming and setting seed all year. The flowers draw insects, which help pollinate them. Plants produce large amounts of seed. Water, animals, people, and farm tools can all spread it. Birds visit thick stands when the seeds ripen. Sources also list seed as the means to grow new plants. This ready spread makes weed control a concern where it grows.

Wild plants grow in both wet and dry thickets and fields. They also grow in hedges and on waste ground. In Australia, they grow as weeds in open forest under heavy grazing. Records also place them in monsoon forest and vine thickets. The species can form broad, dense stands. These records show many habitats, not exact garden care needs. The sources give no frost limits or hardiness zones. They give no clear guidance on pests or disease.

Records note the use of seeds in drinks with water and sugar. Folk remedies use the roots, leaves, and plant in bloom. Reported uses include stomach troubles, fevers, and skin problems. These folk uses do not prove that treatment is safe or works. The leaves contain essential oil and help repel bedbugs. The oil has also shown an ability to kill insects. Useful Tropical Plants reports no known hazards. That does not prove it is safe for pets or use as medicine.