Polygala sanguinea (Blood Milkwort)

Plant Info
Also known as: Purple Milkwort, Field Milkwort
Family:Polygalaceae (Milkwort)
Life cycle:annual
Habitat:sun; moist; fields, bogs, fens
Bloom season:July - September
Plant height:4 to 12 inches
Wetland Indicator Status:GP: FACW MW: FACU NCNE: FACU
MN county distribution (click map to enlarge):Minnesota county distribution map
National distribution (click map to enlarge):National distribution map

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Detailed Information

Flower: Flower shape: indistinct Flower shape: irregular Cluster type: spike

[photo of flowers] A cylindrical spike, ½ inch across elongating up to 1 inch long with maturity. Individual flowers have 2 outer petal-like sepals that are large, egg-shaped and wing-like, resembling fish scales from the outside. 3 small petals form a narrow tube in the center with 8 tiny yellow-tipped stamens. Flower color ranges from purple to rose pink, fading to greenish white with age. One plant usually has a few to many clusters at the end of branching stems.

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

[photo of leaves] Leaves are up to 1½ inches long and very narrow, hairless and toothless, with pointed tips and little or no stalk. There is a prominent vein down the center. The stem is angular, hairless, unbrached or branching in the upper plant.

Fruit: Fruit type: capsule/pod

Fruit is a small round capsule containing 2 hairy seeds.


The flowers are similar to those of the related Cross-leaved Milkwort (Polygala cruciata), which is far less common though they may be growing side by side; it has leaves typically whorled in 4s and is shorter statured.

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More photos

Photos by K. Chayka taken in Blaine, Anoka County. 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: Ian - St. Paul
on: 2014-07-21 14:46:31

Saw this out in Belwin prairie near Afton. Unusual place for it given it's preferred habitat (Belwin is quite sandy), but there was evidence of standing water around.

Posted by: Brian - St. Peter
on: 2015-07-21 22:57:00

There's a great display of this species right now at many places on the main rock outcrop area far along the trail from the southern entrance to Louisville Swamp in Scott County.

Posted by: Ivan - Wing River Twp Wadena Co.
on: 2019-09-05 14:03:34

I have Photo if needed. Found doing survival check in tree planting. 9/4/19

Posted by: Barbara H Fleischman - Elgin
on: 2021-10-09 15:03:21

I saw this plant in the fen area in Chester Woods Park, east of Rochester. Blooming 10-6-21. Other plants around it included strawberry, violets, and bottle gentian.

Posted by: Rachel Rusten - Kittson County
on: 2022-06-29 10:11:59

I saw this in bloom 07-06-21 in Skull Lake WMA east of Hallock, MN. I posted on iNaturalist and found this was the most northernmost occurrence of this species to be recorded

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