Yellow milkwort flower

Yellow milkwort

Pictured above: Yellow milkwort (Polygala rugelli) by John Moran. Click on terms for botanical definitions. View post as a PDF.

Also known as Rugel’s milkwort, Yellow milkwort (Polygala rugelii) is an annual herbaceous wildflower endemic to the Florida peninsula. Its showy flowers are bright yellow and borne in compact, thimble-shaped clusters. They are solitary and have large, lateral sepals. Leaves are alternately arranged and have smooth margins. Upper leaves are small and lanceolate in shape; lower leaves are large, obovate to spatulate, and appear as a rosette.

Yellow milkwort blooms primarily in summer and fall, but it has throughout most of the year. It occurs naturally in wet pine flatwoods.

Yellow milkwort (Polygala rugelli) by Mary Keim

The name Polygala comes from the Greek polys, which means “many or much,” and gala, which means “milk.” It is so-named because it was once believed that the presence of Polygala species in cow fields would result in higher milk production. The species name, rugelii, refers to the British-born botanist and physician, Ferdinand Rugel (1806-1879), who collected and named many plants throughout the southeastern US.

Family: Polygalaceae (Milkwort family)
Native range: Peninsular Florida
To see where natural populations of yellow milkwort have been vouchered, visit
Growth habit: 1–3’ tall
Propagation: Seeds, root division
Garden tips: You’ll have to visit a natural area to see this little jewel as it is not commercially available in plant or seed form.

For more information on other Polygala species, see these resources: