Polygala lutea - Orange Milkwort. Grown for its flashy orange flowers, the Orange Milkwort is classified as a biennial or short-lived perennial. It should be allowed to self-seed, in order to establish itself. At home in bog gardens, this species likes full sun to about 40% shade and wet to damp soil (not flooded). We grow these in the same soil as Sarracenia, Calopogon and most bog plants: 1/3 sand plus 2/3 peat moss. Plant with the crown and leaves above soil (barely), and water well to settle the soil around the thin roots. Keep weeds and moss away from the plants as the seedlings prefer bare peat/sand to germinate. In USDA zones 6 and colder, a winter mulch of pine needles may help; remove these by April. We have over wintered Orange Milkwort easily in zone 7-6, but are not sure how far north it will tolerate beyond these zones.
Young plants can be moved any time the ground is not going to freeze. As is true with most biennials, blooming plants often die after setting seed, so do not transplant blooming plants or worry if older plants die. It has been our experience that this species is easy to establish as small colonies that are welcome and non-competitive “weeds”. Fertilizer isn’t needed.