How to Grow Sundial White
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Sundial White
Impatiens walleriana 'Sundial White'
flowerSundial White is a compact, early-flowering impatiens cultivar known for its pure white blooms and mounding growth habit. It grows 10-12 inches tall and produces abundant flowers from early summer through frost. This variety is prized for its reliability, disease resistance, and ability to thrive in shaded garden spaces.
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Example Sundial White timeline · Pittsburgh, PA (Zone 6b)
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Plant Sundial White
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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First Sundial White blooms
Around May 22≈ 35 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Sundial White dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 9-11; grown as an annual in cooler zones
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Seedling
2-3 weeksTiny cotyledons emerge and develop first true leaves. Plants are delicate and light green.
Provide bright indirect light, maintain high humidity, keep soil moist but not soggy, maintain 70-75°F temperature.
Vegetative Growth
3-4 weeksPlants develop branching stems and multiple leaves. Growth is bushy and compact as variety naturally mounds.
Pinch tips when 2-3 inches tall to encourage branching. Begin light fertilizing every 2 weeks with balanced fertilizer.
Early Flowering
2-3 weeksFirst flower buds appear at branch tips. Early blooms are abundant and pure white with characteristic impatiens shape.
Continue regular watering and moisture. Apply balanced to slightly higher-phosphorus fertilizer bi-weekly to support blooming.
Peak Flowering
8-12 weeksPlant is covered in white flowers from top to bottom. Foliage remains full and healthy green.
Deadhead spent flowers to encourage continuous blooming. Maintain consistent moisture. Monitor for pests and diseases.
Continued Blooming & Decline
Until first frostFlowering continues until frost in fall. Plants may become leggy if not maintained; foliage can thin.
Light pruning can rejuvenate plants mid-season. Continue deadheading. Reduce watering slightly in fall. Frost kills tender plants.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Increase humidity, mist foliage regularly, apply insecticidal soap or neem oil if infestation occurs. Avoid overhead watering on leaves.
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Use yellow sticky traps, apply insecticidal soap or neem oil, ensure good air circulation. Check undersides of leaves regularly.
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Spray with strong water stream, use insecticidal soap, apply neem oil. Encourage beneficial insects.
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Improve air circulation, avoid wetting foliage, remove infected leaves immediately, apply fungicide if severe. This is the most serious disease for impatiens.
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Reduce humidity, improve air circulation, remove diseased leaves, avoid overhead watering. Apply fungicide for severe infections.
Uses
Not for consumption
CulinaryImpatiens flowers and foliage are not edible and should not be consumed. [source]
Cut flowers and floral arrangements
HouseholdPure white flowers are elegant in small arrangements or as accent flowers in mixed bouquets. Flowers are delicate and short-lived once cut. [source]
Pollinator nectar source
WildlifeFlowers attract hummingbirds and butterflies, providing nectar during summer and fall when other flowers may be limited. [source]
Shade garden design
CraftSundial White is invaluable for brightening shaded borders and woodland gardens, creating visual contrast with darker foliage plants. [source]
Container and bedding displays
HouseholdCompact mounding habit makes it ideal for hanging baskets, window boxes, mixed containers, and dense bedding displays. [source]
Harvest Tips
Not a harvest plant—grown entirely for ornamental flowers. Deadhead spent blooms regularly by pinching or cutting below the flower to encourage continuous flowering throughout the season. Flowers can be cut for short-lived fresh arrangements if desired.
Fun Facts
- 🌱 The name 'Impatiens' comes from the plant's seed pods, which explosively release seeds when touched when ripe—the plant is quite literally impatient to spread its offspring.
- 🌱 Sundial series impatiens were bred for earlier and more abundant flowering than standard impatiens, often blooming 2-3 weeks earlier than traditional varieties.
- 🌱 The pure white color of Sundial White makes it particularly effective in shade gardens where it appears to glow in dim light, earning impatiens the nickname 'busy lizzie' for their non-stop blooming habit.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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