Yerba mansa (Anemopsis californica) is a perennial from the Lizard’s tail family, Saururaceae, a family of aromatic herbs. This family is classified into the Magnoliid clade, which produces primitive flowers distinct from monocots and dicots. A. californica is the only species in the genus Anemopsis.
This plant’s distribution lies mostly within the southwest region of the United States, found as far north as Oregon and as far east as Oklahoma. Its range also extends into northern Mexico. Yerba mansa is most often found growing in alkaline, marshy habitats, including salt grass flats and valleys. During the warm months, it is easily identifiable due to its notable blooms and because it emits an unmistakable spicy or peppery aroma.
At first glance, it appears to produce flowers with distinct white petals. However, the flowers do not contain true petals – these petal-like structures are actually bracts, or modified leaves that surround the flower cone. These bracts are cheaper (less energy-intensive) for the plant to create than flowers, and achieve much the same purpose of drawing in pollinators. Each cone spike contains as many as one hundred tiny white “flower,” which will later form brown seed capsules.
“Yerba” comes from “hierba,” the Spanish word for herb, while “mansa” means tame or calming, thus giving it the name “calming herb.” Another common name for it is bear root.
Yerba Mansa Growth, Hardiness & Climate
Yerba mansa is hardy and tolerant of saline and alkaline conditions. It grows best in poorly draining soils. Although it is found in a variety of wetland conditions, yerba mansa is frequently associated with geothermal springs and is even considered to be an indicator of their presence, especially in semi-arid environments.
Yerba mansa grows low to the ground, only reaching heights of about 1 foot tall. It will instead devote more of its energy to growing in a carpet-like manner, spreading 2 to 3 feet wide. It blooms its unique flower cones described above in the spring. Yerba mansa is unable to self-pollinate and relies on native pollinators for cross-pollination. It can also propagate asexually through its creeping underground rhizomes.
How to Plant Yerba Mansa In Ponds
As it requires permanently moist soil, yerba mansa will thrive on the edge of a garden pond or in a bog garden. It provides great groundcover and can be planted anywhere you want to fill in empty spots in your garden! It can also do well under a tree that requires a lot of watering, or even on its own as a container plant.
It can be planted by seed or by division. Seed germination is heat dependent, and can take several weeks depending on the outside temperature. In the wild, temperatures up to 38°C/100°F are thought to trigger germination. For more control over germination, seeds can be started indoors on a heated seed starting mat or in a very warm area of the house. Transplant seedlings outdoors after the threat of frost has passed. To ensure germination, one must also keep soil wet, or even submerge the seeds in shallow water.
How to Care For Yerba Mansa
Yerba mansa is easy to care for once established. Keep the soil moist year-round with regular watering. At the end of the season (late summer), it is okay to let it dry out by lessening watering as the plant becomes dormant.
How to Winter Yerba Mansa
In late summer, you will notice yerba mansa’s leaves begin to change colors to rich autumnal colors like red and purple! It will then naturally become dormant starting in the fall, and will resume growth from its roots again in the spring. You can cut back the leaves as they die off in the winter to keep your garden looking clean.
Is Yerba Mansa Toxic, Poisonous or Invasive?
Yerba mansa can be somewhat invasive due to its tendency to grow at a rapid rate. It can crowd out other plants, so it may need to be maintained so that it doesn’t dominate your water garden. It is not known to be toxic to humans or animals.
Is Yerba Mansa Edible? Will Fish Eat it?
While it was historically used as medicine more than food, the roots are edible either cooked or raw. Some Native American tribes used the seeds to add a substitute pepper flavor to cooking as well.
Pond fish likely won’t interact with it since it is not a fully aquatic plant, although they might taste seeds that fall into a pond. This should not be harmful to your fish, as yerba mansa is not known to be toxic to humans or animals.
Yerba mansa is also known to be a deer resistant plant, so it can be used to protect your garden from herbivory by planting it as a border.
Where to Buy Yerba Mansa & Seeds? (UK & US)
Seeds can be purchased by shopping online or in person at a nursery. As a fairly popular garden pond plant, you shouldn’t have too much difficulty in finding it, but it can typically be specially ordered by most nurseries if needed.
Hi! I am having great success with these plants in floating planters in our pond at 8,500′ in the Colorado Rockies. Our pond will freeze over so I am wondering if I can bring them inside our garage in a tank of water for over wintering? If not, what do I do?
We planted our Yerba Mansa in the ground in its pot overwinter in Pennsylvania and placed leaf litter then cedar chip mulch on top of it. It has now come back nicely this spring and we’re putting it back on a margin top shelf in our pond now.
Our true floating tropical plants like Neptune’s Crown we left to the tub with several windows facing southeast overwinter.
Is it okay to have the plant in it’s container partially submerged in water about 4” above the submerged pot? Water is covering about 2” the bottom of the plant.
I’m wondering because some leaves are now over bent over and in the water while other middle leaves are sticking straight up. Perhaps that is due to the 50* weather in the mornings.