How to Grow Purple Gleam
Purple Gleam
Tropaeolum majus 'Purple Gleam'
flowerPurple Gleam is a double-flowered nasturtium cultivar prized for its rich, velvety purple blooms that contrast beautifully with vibrant green foliage. It's a compact, bushy annual that flowers prolifically throughout the growing season. The semi-double to double flowers are ideal for cut arrangements and garden display.
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Example Purple Gleam timeline · Pittsburgh, PA (Zone 6b)
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Plant Purple Gleam
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 Purple Gleam blooms
Around Jun 6≈ 50 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Purple Gleam dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 2-11 as an annual; prefers cooler to moderate climates
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Germination & Seedling
10-14 days for germination, 3-4 weeks until transplant-readySeeds sprout within 10-14 days; seedlings develop round cotyledons followed by distinctive peltate (shield-shaped) leaves
Keep soil warm (65-70°F) and moist. Provide bright light to prevent leggy growth. Thin or transplant when first true leaves appear.
Vegetative Growth
3-4 weeks after transplantingPlant develops bushy form with multiple stems and abundant green foliage. Leaves are round, peltate, and bright green with prominent veins.
Provide moderate fertilizer (avoid high nitrogen which promotes foliage over flowers). Pinch growing tips to encourage branching. Water regularly.
Budding & Flowering
6-12 weeks (continues until frost)Buds form in leaf axils; double purple flowers emerge with ruffled petals. Flowers are 1.5-2 inches wide and velvety in appearance.
Deadhead spent blooms regularly to encourage continuous flowering. Maintain consistent moisture and moderate feeding. Support stems if needed.
Peak Bloom & Maintenance
8-10 weeks (or until first frost)Plant is covered with flowers; foliage remains lush and green. Multiple flowers open daily.
Continue deadheading. Monitor for pests and diseases. Water during dry spells. Reduce watering slightly if you want seeds.
Seed Formation & End of Season
4-6 weeks until frostIf not deadheaded, flowers set distinctive three-lobed seed pods. Foliage may fade as temperatures drop in fall.
Allow some flowers to remain if you want to collect seeds. Frost will kill the plant; pull and compost after frost.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with strong water stream; use insecticidal soap or neem oil; encourage beneficial insects like ladybugs
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Remove affected leaves; apply reflective mulch; use yellow sticky traps; spray neem oil or insecticidal soap
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Increase humidity and water at soil level; spray with miticide or neem oil; remove heavily infested leaves
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Hand-pick; use Bacillus thuringiensis (Bt); remove and destroy infected foliage
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and
Remove debris; set beer traps; hand-pick at night; use diatomaceous earth barriers
Uses
Edible Flowers & Peppery Garnish
CulinaryThe velvety purple petals are completely edible and add a beautiful, peppery flavor to salads, soups, and dessert garnishes. The flowers are popular in modern cuisine for their visual appeal and unique taste. [source]
Seed Pods & Capers
CulinaryYoung green seed pods can be pickled like capers and add a tangy, spicy element to dishes. They provide a creative and flavorful alternative to traditional capers. [source]
Cut Flowers & Arrangements
HouseholdThe double purple blooms are excellent for fresh flower arrangements, adding rich color and texture. They pair well with greenery and other cut flowers. [source]
Traditional Remedies & Vitamins
MedicinalNasturtium flowers and leaves have been used in traditional herbalism for their vitamin C content and antimicrobial properties. They are often brewed as a tea or used in herbal preparations. [source]
Pollinator Attraction
WildlifePurple Gleam flowers attract bees, hummingbirds, and other pollinators while serving as a trap crop for aphids, protecting nearby vegetables. This makes it excellent for supporting garden biodiversity. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Purple Gleam nasturtiums are grown primarily as ornamental flowers. Cut stems with blooms in early morning when stems are turgid; they last 5-7 days in a vase. Flowers can be harvested continuously by deadheading (removing spent blooms) to promote more flowering. All parts are edible—petals add a peppery flavor to salads. Seeds can be collected when pods turn brown (typically late summer to early fall).
Fun Facts
- 🌱 The name 'nasturtium' comes from Latin 'nasus tortus' (twisted nose), referring to the peppery scent that can make one's nose twitch!
- 🌱 Purple Gleam's double flowers are a horticultural achievement—wild nasturtiums have single flowers, and the doubling creates extra petals by converting stamens into petal-like structures.
- 🌱 Nasturtiums have been grown since Elizabethan times and were called 'Indian cress' by early Europeans who traded with explorers returning from the Americas.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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