How to Grow President Grevy
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President Grevy
Dahlia × hybrida 'President Grevy'
flowerPresident Grevy is a stunning decorative dahlia cultivar prized for its large, fully double flowers with deep purple-red petals and intricate layered form. These showstopping blooms can reach 6-8 inches in diameter and are excellent for cut flowers and garden display. The plant grows as a tender perennial with tuberous roots, typically reaching 3-4 feet in height.
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Example President Grevy timeline · Pittsburgh, PA (Zone 6b)
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Plant President Grevy
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 President Grevy blooms
Around Jul 16≈ 90 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact President Grevy dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 8b-10; in colder zones (3-8a), grow as an annual or dig tubers in fall for storage
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Get my President Grevy timeline →Growth Stages
Sprouting
2-3 weeksTubers begin to show shoots 2-3 weeks after planting. Emerging growth appears as reddish sprouts breaking through soil.
Ensure soil is warm (65-70°F) and consistently moist. Provide support stake if planting in windy location. Keep area weed-free.
Vegetative Growth
4-6 weeksPlant develops foliage with compound leaves and stems elongating. Bushy growth forms with multiple branching points.
Water regularly and deeply. Apply balanced fertilizer every 2-3 weeks. Pinch back the main stem when plant reaches 12 inches to encourage bushier growth and more flowers. Remove lower leaves if needed for air circulation.
Budding & Early Flowering
3-4 weeksFlower buds appear at stem terminals. Initial blooms open, revealing the characteristic full double form and deep purple-red color.
Switch to higher-phosphorus fertilizer to support blooming. Remove side buds if larger blooms are desired, or leave them for continuous smaller flowers. Deadhead spent flowers regularly.
Peak Bloom
8-12 weeksPlant produces abundant large, fully double flowers (6-8 inches) with rich purple-red coloring and intricate petal layering. Foliage remains healthy and vibrant.
Maintain consistent watering and feeding schedule. Stake and tie plants if needed for support. Cut flowers regularly for vases to encourage more blooming. Monitor for pests and diseases.
Senescence & Dormancy
4-8 weeksFlowering gradually decreases as temperatures cool in fall. Foliage yellows and dies back after first frost (or planned removal).
In zones 8b-10, allow foliage to remain until after first frost to strengthen tubers. In colder zones, dig tubers after foliage dies, clean, and store in cool, dry location (40-50°F) for winter. Reduce watering significantly.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick beetles early morning; use neem oil or insecticidal soap; remove affected foliage; plant marigolds as deterrent
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Increase humidity by misting; use strong water spray to dislodge; apply neem oil or miticide if severe; ensure good air circulation
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Remove affected flowers; use blue sticky traps; apply neem oil or spinosad; avoid excessive nitrogen fertilizer
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Use yellow sticky traps; spray with insecticidal soap; apply neem oil; encourage natural predators like ladybugs
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and
Hand-pick at night; use beer traps or copper barriers; apply diatomaceous earth; remove shelter like leaf litter
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Improve air circulation; avoid overhead watering; apply sulfur dust or fungicide; remove affected leaves; plant in full sun
Uses
Edible Flower Garnish
CulinaryDahlia petals are edible and add striking visual appeal to salads, desserts, and beverages. The petals have a slightly sweet, mild flavor and can be used to decorate cakes and plates. [source]
Cut Flower Arrangements
HouseholdPresident Grevy is exceptional for floral design, adding dramatic impact to cut flower arrangements, wedding bouquets, and decorative displays. Its large, fully double blooms serve as excellent focal flowers. [source]
Flower Pressing & Drying
CraftThe large petals can be pressed flat for botanical art projects, scrapbooking, or dried for potpourri and decorative crafts. The deep color is retained well through the drying process. [source]
Pollinator Support
WildlifeWhile fully double cultivars produce less nectar than single dahlias, the flowers still attract butterflies, bees, and other pollinators to the garden throughout the growing season. [source]
Traditional Herbal Use
MedicinalIn traditional herbalism, dahlia tubers have been used in some cultures for their potential anti-inflammatory properties, though scientific evidence is limited. More research is needed on medicinal applications. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Cut flowers in early morning when fully open but petals are still firm. Cut stems at 45-degree angle and immediately place in cool water. Cut frequently (every few days) to encourage continuous blooming throughout the season. Flowers typically last 7-10 days in a vase with fresh water and flower food.
Fun Facts
- 🌱 President Grevy dahlias were named after French President Jules Grévy in the 19th century, reflecting the plant's status as a showstopper variety worthy of such recognition.
- 🌱 Dahlias have tuberous roots that multiply each year, allowing gardeners to divide and propagate plants, with a single tuber potentially producing dozens of new plants over time.
- 🌱 The dahlia is the national flower of Mexico, where wild dahlia species originated and have been cultivated for centuries, with evidence of their use dating back to the Aztec era.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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