How to Grow Brunnera Jack Frost

Brunnera Jack Frost

Brunnera Jack Frost

Brunnera macrophylla 'Jack Frost'

flower

Jack Frost is a stunning cultivar of Siberian bugloss featuring heart-shaped leaves heavily variegated with silver, creating a frosted appearance that persists throughout the growing season. This shade-loving perennial produces delicate blue forget-me-not-like flowers on slender stems in spring. It's an excellent choice for brightening dark garden spaces while requiring minimal maintenance.

Growing Conditions

☀️
Sun: Partial to full shade, ideally 2-4 hours of dappled sunlight daily
💧
Water: Moderate watering, keeping soil consistently moist but not waterlogged. Water at soil level to prevent leaf spotting. Once established, fairly drought-tolerant, but perform best with regular moisture during growing season.
📏
Spacing: 18 inches
📅
Days to maturity: Establishes within 1-2 seasons
🌱
Planting depth: Crown at soil level; do not bury the crown

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.0-7.0
Amendments:
Compost Peat moss or leaf mold Perlite for drainage

Growing Zones

Find your zone →

Thrives in zones 3-8, with best performance in zones 4-7

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a

Sign up to see your zone highlighted.

Growth Stages

1

Dormancy

November-March

Plant dies back completely in late fall after first frost. Underground rhizomes remain alive.

Cut back dead foliage to ground level. Mulch lightly with 1-2 inches of compost to protect rhizomes over winter.

2

Spring Growth

March-April

New foliage emerges with distinctive silver-frosted variegation on heart-shaped leaves. Growth is rapid once soil warms.

Remove winter mulch gradually as temperatures warm. Apply balanced fertilizer as growth begins. Ensure adequate moisture during this stage.

3

Flowering

April-May

Delicate blue forget-me-not-like flowers appear on wiry stems above the foliage, creating an airy, cottage-garden look.

Deadhead spent flowers to encourage longer blooming. Support tall stems if needed in windy locations. Flowers are excellent for cutting.

4

Summer Growth

June-August

Foliage reaches full size and the silver variegation becomes more pronounced. Plant maintains dense mounding habit. Flowers fade and seed heads develop.

Keep soil consistently moist during hot spells. Remove seed heads if self-seeding is not desired (variegated seedlings often revert). Monitor for powdery mildew in humid conditions.

5

Fall Senescence

September-November

Foliage begins to yellow and decline as temperatures cool. Plant prepares for dormancy.

Reduce watering as plant naturally dries down. Do not fertilize. Allow seed heads to remain if wildlife feeding is desired.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Aggressive spreaders like Mint or Liriope Plants requiring full sun Shallow-rooted competitors requiring frequent watering

Common Pests

  • Ensure good air circulation. Water at soil level only. Apply sulfur dust or neem oil spray if needed. Avoid wetting foliage. Remove affected leaves.

  • and

    Handpick early morning or evening. Provide copper tape barriers around planting area. Use slug bait or beer traps if population is heavy.

  • Prune out affected foliage. Spray with insecticidal soap on undersides of leaves. Encourage beneficial wasps with native plantings.

  • Remove infected leaves promptly. Improve air circulation. Water only at soil level. Apply copper fungicide if severe.

Uses

🍳

Edible garnish

Culinary

Young leaves and flowers are edible with a mild cucumber-like flavor and can be used as delicate garnishes for salads and cocktails. [source]

🏠

Cut flowers and arrangements

Household

The delicate blue flowers and frosted silver foliage make excellent additions to spring floral arrangements, bringing shade-garden beauty indoors. [source]

🦋

Pollinator support

Wildlife

Flowers attract bees, butterflies, and other beneficial insects early in the season when food sources are scarce, supporting early pollinator populations. [source]

🎨

Shade garden design

Craft

The striking silver variegation makes it invaluable for brightening shaded areas and adding visual interest to woodland and shade gardens without requiring supplemental lighting. [source]

💊

Traditional herbal use

Medicinal

Brunnera species have been used in traditional Siberian medicine for respiratory and digestive support, though scientific evidence is limited and modern use is primarily ornamental. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

This ornamental plant is not harvested for food. Cut flowers for arrangements by snipping stems above a leaf node in the morning after dew dries. Flowers last 1-2 weeks in water. Allow some flowers to mature into seed heads for fall interest. Foliage remains attractive throughout the growing season and can be enjoyed as part of shade garden displays.

Fun Facts

  • 🌱 The 'Jack Frost' name refers to the distinctive silver frosting effect on the leaves, which actually intensifies as temperatures cool in spring and fall, making the plant more ornamental in cooler seasons.
  • 🌱 Unlike many variegated plants that lose their coloring in shade, Jack Frost's silver variegation is actually more vivid in deeper shade, making it one of the best variegated foliage plants for low-light garden areas.
  • 🌱 Brunnera is sometimes called 'Siberian bugloss' and is native to Siberia, Caucasus, and Turkey, thriving in cool mountain forest understories where it evolved to brighten dark woodland floors with its frosted foliage.

Want personalized planting timelines?

Sign up to get frost dates, task lists, and more for your zone.

Get started free