Acalypha rhomboidea (Three-seeded Mercury)

Plant Info
Also known as: Rhombic Copperleaf
Family:Euphorbiaceae (Spurge)
Life cycle:annual
Habitat:part shade, sun; disturbed soil, waste places
Bloom season:June - October
Plant height:8 to 24 inches
Wetland Indicator Status:GP: FACU MW: FACU NCNE: FACU
MN county distribution (click map to enlarge):Minnesota county distribution map
National distribution (click map to enlarge):National distribution map

Pick an image for a larger view. See the glossary for icon descriptions.

Detailed Information

Flower: Flower shape: indistinct Cluster type: whorled

[photo of flowers] Tiny petal-less flowers form in dense clusters of palmately lobed, leafy bracts at the leaf axils, with separate male and female flowers. The yellowish to brown male (staminate) flowers are on a short stalk with 2 to 3 green female (pistillate) flowers at the base of the stalk in the center of bract. The lobes of the bracts are irregular, lance-like with pointed tips. ranging in color from light green to deep coppery-red and may be smooth but often with scattered hairs, especially along the edges and undersides.

Leaves and stems: Leaf attachment: alternate Leaf type: simple

[photo of leaves] Leaves are 1 to 4 inches long, up to 1 inch wide, mostly oval to lance-like tending towards rhombic angles, sparsely hairy, with long slender stalks that can be more than half as long as the leaf blade. The edges are serrated with shallow, blunt teeth. Leaves may appear almost whorled at the end of the stem but they are merely tightly packed, alternately attached. Leaves are typically medium to dark green but the plant can become deep coppery red, especially the stems, bracts and undersides of leaves. Stems are erect, hairless or somewhat hairy, mostly unbranched with the occasional short flowering side branches.


Three-seeded Mercury is a common native of abandoned lots, roadsides, railroads, and disturbed soil. A number of plants volunteered in my own backyard garden. It is generally considered a weedy species, but does not take over areas like invasive species do. Pennsylvania Pellitory (Parietaria pensylvanica) is similar in structure, but is a smaller plant with toothless leaves.

Please visit our sponsors

  • Minnesota Native Plant Society

Where to buy native seed and plants ↓

Map of native plant purveyors in the upper midwest

  • Itasca Ladyslipper Farm - Native orchids, container grown
  • Prairie Restorations - Bringing people together with the land
  • Shop for native seeds and plants at!
  • Shooting Star Native Seeds - Native Prairie Grass and Wildflower Seeds
  • Morning Sky Greenery - Native Prairie Plants

More photos

Photos courtesy Peter M. Dziuk taken in Anoka County.


Have you seen this plant in Minnesota, or have any other comments about it?

Posted by: Elizabeth - Grey Cloud Island Township
on: 2015-08-26 22:14:06

I looked through every plant in Peterson's guide to wildflowers and finally found it and checked it against your site. Thanks. These are in many locations in my yard.

Posted by: Kenny h - East of rose creek on shooting star trail
on: 2017-07-31 08:30:21

Have been beating my head against the wall for years on this plant...finally got it...joined a plant discussion group on Facebook...its been in my landscaping around our house for years...its a little comforting to know that it is native.

Post a comment

Note: All comments are moderated before posting to keep the riff-raff out. An email address is required, but will not be posted—it will only be used for information exchange between the 2 of us (if needed) and will never be given to a 3rd party without your express permission.

For info on subjects other than plant identification (gardening, invasive species control, edible plants, etc.), please check the links and invasive species pages for additional resources.


Note: Comments or information about plants outside of Minnesota and neighboring states may not be posted because Id like to keep the focus of this web site centered on Minnesota. Thanks for your understanding.