Brunnera macrophylla 'Frost King', commonly sold as Siberian Bugloss 'Frost King', gives you a luminous shade perennial built around foliage. Huge heart-shaped leaves are washed in silver with prominent green veins, creating a bright mound about 14 to 16 inches tall and 22 to 24 inches wide. In spring, airy sprays of small blue forget-me-not flowers hover over the leaves before the foliage becomes the main display.
Use this plant where you want long-season contrast in part shade to full shade: along woodland paths, in cool courtyard beds, beside hostas and ferns, or at the front of a mixed shade border. The pale leaf surface reflects low light, so one plant can brighten a corner and a group can form a soft groundcover effect. It also works well in containers that receive morning light and afternoon protection.
Plant Brunnera macrophylla 'Frost King' in fertile, evenly moist, well-drained soil. It appreciates organic matter, mulch, and protection from hot afternoon sun, especially in warm climates where leaves can scorch. Keep the root zone from drying out during the first season and during summer heat. Good drainage is still important, because constantly soggy soil can weaken the crown.
Maintenance is light. Remove tattered leaves as needed, then clean up old foliage in spring as fresh growth appears. The rough, hairy leaves help make the plant deer and rabbit resistant, and the early blue flowers can add welcome color before many shade perennials fully expand. With steady moisture and a cool site, you get a refined silver mound that ties together ferns, heucheras, hostas, hellebores, and other shade companions.