How to Grow Sundial Bicolor
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Sundial Bicolor
Helianthus annuus 'Sundial Bicolor'
flowerSundial Bicolor is a dwarf sunflower variety that reaches 12-18 inches tall, making it ideal for containers and small gardens. It produces charming bicolor blooms with golden-yellow petals and deep burgundy or mahogany centers, resembling a sundial. This compact cultivar maintains the cheerful sunflower character while being manageable for tight spaces.
When should you plant Sundial Bicolor in your zone?
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Example Sundial Bicolor timeline · Pittsburgh, PA (Zone 6b)
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Plant Sundial Bicolor
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 Bicolor blooms
Around Jun 26≈ 70 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Sundial Bicolor dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 2-10; annual grown nationwide
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Seedling
2-3 weeksCotyledons emerge within 7-10 days; first true leaves appear shortly after.
Keep soil consistently moist but not waterlogged. Provide bright light immediately. Thin seedlings to proper spacing if direct seeding.
Vegetative Growth
3-4 weeksPlant develops 4-6 true leaves and establishes a compact, bushy form; stems thicken and become sturdy.
Reduce watering frequency. Pinch growing tip at 6-8 inches tall to encourage branching and more flowers. Support with light staking if needed.
Budding
2-3 weeksFlower buds form at branch tips; plant reaches near full height (12-18 inches) with dense foliage.
Maintain even moisture. Apply balanced fertilizer every 2-3 weeks. Monitor for pests and mildew, especially in humid conditions.
Flowering
4-6 weeksBicolor blooms open with bright yellow petals and deep burgundy centers; flowers are 2-3 inches across.
Continue regular watering and feeding. Deadhead spent flowers to encourage more blooms. Support heavy flower heads if necessary.
Seed Development & Maturation
2-3 weeksPetals fade and drop; seed head develops full size with mature seeds visible in the center disk.
Reduce watering as plant naturally enters dormancy. Leave seed heads on plant for wildlife, or harvest for seeds before birds consume them.
Common Pests
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Hand-pick beetles and eggs; use neem oil spray; encourage beneficial insects; remove plant debris.
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Spray with water to dislodge; use insecticidal soap; introduce ladybugs; neem oil application.
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Improve air circulation; avoid overhead watering; apply sulfur or potassium bicarbonate spray; remove affected leaves.
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Increase humidity with water spray; use neem oil; introduce predatory mites; ensure adequate watering.
Uses
Edible seeds
CulinarySunflower seeds are nutritious snacks rich in vitamin E, selenium, and healthy fats. Seeds can be roasted, salted, or used in baking. [source]
Cut flower arrangements
HouseholdThe compact, bicolor blooms are perfect for small bouquets, vases, and floral arrangements. Their manageable size works well in intimate displays. [source]
Pollinator support
WildlifeSunflowers attract bees, butterflies, and beneficial insects to the garden. Leaving seed heads standing provides food for goldfinches and other seed-eating birds. [source]
Drying & pressing
CraftFlowers dry beautifully for dried arrangements, pressed flower crafts, and potpourri. The bicolor pattern is striking when preserved. [source]
Herbal teas & extracts
MedicinalSunflower petals and leaves have been used in traditional herbal preparations; petals can be steeped for a light tea. Contains compounds with anti-inflammatory potential. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
For cut flowers, harvest in early morning when petals are fully open but still turgid; cut stems at 45-degree angle and immediately place in water. For seeds, wait until the back of the seed head turns brown/tan, then cut the entire head and hang upside down indoors to dry for 2-3 weeks before extracting seeds.
Fun Facts
- 🌱 Sunflower heads exhibit heliotropism when young, tracking the sun's movement across the sky from east to west during the day—a behavior absent in mature Sundial Bicolor due to their fixed, compact form.
- 🌱 The name 'Sundial' refers to the radial disk florets in the center, which resemble numbers on a clock face and create a sundial-like appearance.
- 🌱 Sunflowers are allelopathic, meaning they release compounds that inhibit growth of nearby plants; this is why spacing and companion planting are important in the garden.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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