How to Grow Red Cleome
Red Cleome
Cleome hassleriana
flowerRed Cleome, also called Spider Flower, is a tall annual ornamental plant with dramatic deep red or crimson flowers arranged in showy clusters. The plant features distinctive spidery stamens and seed pods that extend beyond the flower petals, creating an exotic, airy appearance ideal for cottage gardens and cut flower arrangements.
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Example Red Cleome timeline · Pittsburgh, PA (Zone 6b)
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Plant Red Cleome
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 Red Cleome blooms
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Red Cleome dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 2-11 as an annual; prefers warm-season growing in most regions
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Seedling
2-3 weeksDelicate seedlings with two cotyledons and early true leaves emerge within 7-14 days
Keep soil consistently moist but not waterlogged. Provide bright light and maintain 70-75°F temperature. Thin seedlings to prevent damping off.
Vegetative Growth
3-4 weeks after transplantingPlant develops sturdy stems and compound leaves, reaching 1-2 feet tall with bushy lateral branching
Gradually harden off transplants before moving outdoors. Space plants 24 inches apart. Water regularly but allow soil to dry between waterings. No fertilizer needed for healthy soil.
Flowering
6-10 weeks or until first frostClusters of showy red flowers with long, spidery stamens form at stem tips; flowers appear in succession over many weeks
Maintain consistent moisture during flowering. Deadhead spent flowers to encourage continued blooming. Plants are generally self-supporting but may need staking in windy locations.
Seed Pod Development
2-4 weeksAs flowers fade, distinctive thin seed pods develop alongside the remaining flowers, creating ornamental interest
Allow some flowers to mature into seed pods if self-seeding is desired for next season. Pods are particularly attractive in fresh or dried arrangements.
Senescence
Until first frostPlant growth slows and flowering decreases as temperatures drop in fall; plant is killed by first frost
Harvest seeds from mature brown pods before frost. Allow some flowers to remain for wildlife benefit. Pull plants after frost damage.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with neem oil or insecticidal soap; encourage natural predators like ladybugs
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Rinse with strong water spray; apply neem oil or insecticidal soap if infestation is severe
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Increase humidity; spray with miticide or neem oil if populations are high
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and
Hand-pick in early morning; use copper barriers or sluggo-type baits around plants
Uses
Edible Flowers
CulinaryRed Cleome flowers are edible and can garnish salads, desserts, and beverages, adding an exotic spidery visual element and mild flavor. [source]
Cut & Dried Arrangements
CraftThe distinctive flower clusters and seed pods make excellent fresh cut flowers lasting a week indoors, and seed pods dry beautifully for long-lasting arrangements. [source]
Pollinator Attraction
WildlifeRed Cleome attracts butterflies, bees, and hummingbirds with its abundant nectar and is an excellent late-season nectar source for migrating butterflies. [source]
Cottage Garden & Border Filler
HouseholdTall, airy stems create a romantic, naturalistic appearance in cottage gardens, flower borders, and mixed beds without blocking views of shorter plants. [source]
Traditional Herbal Use
MedicinalIn some traditional systems, Cleome species have been used to treat skin conditions and inflammation, 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
Harvest flowers in early morning when stems are fully hydrated for best vase life (5-7 days). Cut stems just above a leaf node to encourage branching. Collect seed pods in late summer/early fall when they turn brown and papery; allow to dry completely before extracting seeds. Self-seeds readily if pods are left on plant.
Fun Facts
- 🌱 Cleome species are called 'Spider Flower' because the long, spidery stamens extending beyond the petals resemble spider legs; the seed pods add to this creepy-crawly appearance.
- 🌱 Red Cleome plants are prolific self-seeders—they can spread freely in gardens and sometimes escape cultivation, naturalize in warm climates, and have become naturalized in parts of tropical and subtropical regions.
- 🌱 The plant was originally native to South America and Africa but is now commonly grown worldwide as an ornamental annual; Victorian gardeners popularized it for its exotic, dramatic appearance.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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