How to Grow Roi Humbert
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Roi Humbert
Canna × generalis 'Roi Humbert'
flowerRoi Humbert is a striking ornamental canna lily cultivar prized for its dramatic dark bronze-burgundy foliage and vibrant red-orange flowers. This tropical-looking perennial grows from rhizomes and produces tall spikes of blooms that attract hummingbirds and butterflies. It's an excellent choice for adding bold color and vertical interest to gardens and containers.
When should you plant Roi Humbert in your zone?
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Example Roi Humbert timeline · Pittsburgh, PA (Zone 6b)
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Plant Roi Humbert
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 Roi Humbert blooms
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Roi Humbert dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 7-11; grow as an annual in cooler zones or dig rhizomes for winter storage
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Dormancy/Planting
4-8 weeks before sproutingRhizomes are stored or planted; may show early bud development
Plant after last frost when soil is warm (65°F+); store dormant rhizomes in cool, dry location in winter
Emergence & Vegetative Growth
4-6 weeksShoots emerge from soil; dark bronze-burgundy leaves unfold and grow rapidly; stems elongate
Water regularly and apply balanced fertilizer every 3-4 weeks; mulch to retain moisture; remove any weak shoots
Bud Formation
2-3 weeksFlower spikes begin forming at stem tips; leaf growth continues; plant reaches full height (4-6 feet)
Continue regular watering and feeding; stake tall plants if needed; ensure full sun exposure
Flowering
6-10 weeks (continues until frost)Vibrant red-orange flowers open sequentially along spikes; dark foliage provides dramatic contrast
Deadhead spent flowers to encourage continued blooming; maintain consistent moisture; fertilize monthly
Dormancy Preparation
Winter monthsFoliage dies back after first frost; rhizomes enter dormancy; growth stops
Cut back stems to 2-3 inches above ground after frost; dig rhizomes, allow to dry, store in cool location; or mulch heavily if leaving in ground in zone 7-8
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick early morning; use pheromone traps away from plants; apply neem oil or pyrethrin if severe
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Increase humidity; spray leaves with water; apply insecticidal soap or neem oil
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Remove affected leaves; apply Bacillus thuringiensis (Bt); maintain plant vigor
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Prune affected stems; apply horticultural oil spray in early spring
Uses
Edible Rhizomes
CulinaryCanna rhizomes are edible and have been cultivated as a food crop, similar to potatoes. They have a slightly sweet flavor and can be boiled, baked, or used in various dishes. [source]
Ornamental Displays
HouseholdThe dramatic burgundy foliage and brilliant red-orange flowers make Roi Humbert ideal for creating tropical-themed gardens, borders, and container arrangements. It serves as a focal point and adds vertical dimension to landscapes. [source]
Hummingbird & Pollinator Attraction
WildlifeThe bright red-orange flowers are highly attractive to hummingbirds and butterflies, making Roi Humbert an excellent choice for pollinator gardens and wildlife-friendly landscapes. [source]
Cut Flowers & Arrangements
CraftThe tall flower spikes and bold foliage are excellent for cut flower arrangements and tropical-themed floral designs, lasting 1-2 weeks in water. [source]
Traditional Uses
MedicinalIn some traditional medicine systems, canna leaves and rhizomes have been used to treat wounds and inflammatory conditions, though scientific evidence is limited. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Cannas are grown for ornamental foliage and flowers, not harvested for consumption. Deadhead spent flower spikes to encourage more blooms. In fall (zones 7-9), dig rhizomes after first frost, allow to dry for several days, remove excess soil, and store in a cool (50-60°F), dry location packed in peat moss or sawdust. In warmer zones, rhizomes can remain in ground year-round.
Fun Facts
- 🌱 Roi Humbert was a beloved Italian opera conductor and composer who lived from 1882-1971; the cultivar was likely named in his honor to reflect its operatic grandeur and dramatic presence.
- 🌱 Canna lilies were brought to Europe from tropical Central and South America in the 16th century and became extremely fashionable during the Victorian era for their bold, exotic appearance.
- 🌱 Roi Humbert's dark burgundy foliage results from high anthocyanin pigment concentration, which also provides some protection from intense sunlight and UV radiation in hot climates.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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