Brunnera ‘Jack Frost’ is a perennial known for its striking foliage and delicate blooms, making it a popular choice for shaded gardens. Its heart-shaped leaves have a silvered, frosted appearance with green veins, giving the plant its name. In spring, small, bright blue, forget-me-not-like flowers emerge. This plant thrives in cooler, shaded environments, offering visual interest throughout the growing season.
Optimal Timing for Cutting Back
Cutting back Brunnera ‘Jack Frost’ enhances its appearance and promotes health. One time is after spring flowers fade, typically late spring or early summer. Removing spent flower stalks (deadheading) prevents seed production and encourages a tidier look, directing energy into foliage.
Another period is late autumn, when foliage declines. Trimming browning or yellowing leaves cleans up the plant, removing pest hiding spots and reducing fungal disease risk. This prepares the plant for dormancy and new spring growth. Some gardeners prefer to leave old foliage for winter protection and cut it back in spring.
Early spring, before new growth, is a final opportunity. Any leaves not removed in fall or damaged by winter can be cut back. This early pruning encourages a fresh flush of new foliage and maintains the plant’s shape.
Reasons and Methods for Cutting Back
Cutting back Brunnera ‘Jack Frost’ improves aesthetics and plant health. Removing spent flowers prevents self-seeding, which helps control plant spread or maintain specific cultivars. This also diverts energy from seed formation to strengthening the root system and supporting foliage.
Use sharp, clean pruning shears for maintenance. When deadheading, cut flower stalks near the base, just above the foliage. Remove damaged, diseased, or yellowed leaves by cutting their petioles close to the crown. This improves air circulation and prevents issues.
If foliage becomes tattered or unsightly, a “renewal prune” can be performed. This involves cutting most foliage to within a few inches of the ground. Typically done in early summer after flowering, this allows the plant to produce a fresh flush of attractive leaves for the rest of the season. The plant recovers quickly with new, vibrant growth.
Post-Cutting Back Care
After cutting back, proper care helps Brunnera ‘Jack Frost’ recover. Water the plant immediately, especially if the soil is dry. Adequate moisture supports recovery and new growth, particularly after a renewal cut.
Consider a light application of balanced, slow-release fertilizer or liquid feed after a major cutback. This provides nutrients for new leaves and stems. Avoid over-fertilizing, as Brunnera generally does not require heavy feeding. Monitor the plant for new growth or stress symptoms like wilting.