How to Grow Crystal Palace Blue Lobelia
Wikimedia Commons
Crystal Palace Blue Lobelia
Lobelia erinus 'Crystal Palace Blue'
flowerCrystal Palace Blue is a compact, mounding annual lobelia prized for its deep blue flowers and bronze-tinged foliage. This dwarf variety reaches only 4-6 inches tall and produces masses of delicate flowers throughout the growing season. It's excellent for edging, containers, hanging baskets, and rock gardens where its cascading habit can shine.
When should you plant Crystal Palace Blue Lobelia in your zone?
Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.
Example Crystal Palace Blue Lobelia timeline · Pittsburgh, PA (Zone 6b)
-
Plant Crystal Palace Blue Lobelia
Around Apr 17Near Pittsburgh's average last spring frost.
-
Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
-
First Crystal Palace Blue Lobelia blooms
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Crystal Palace Blue Lobelia dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives as an annual in zones 3-10; prefers cooler temperatures
Sign up free to see if Crystal Palace Blue Lobelia grows in your zone — and get a personalized planting timeline.
Get my Crystal Palace Blue Lobelia timeline →Growth Stages
Seed and Germination
10-15 daysTiny seeds germinate in 10-15 days under consistent moisture and warm conditions (65-75°F). Seeds are very small and require light to germinate.
Do not bury seeds; press gently into moist soil. Keep under lights or in bright indirect light. Use a humidity dome or plastic wrap to maintain moisture. Bottom heat aids germination.
Seedling
3-4 weeksDelicate seedlings emerge with tiny true leaves. Growth is slow initially; plants remain small and tender. Bronze-tinged foliage begins to develop.
Provide bright indirect light to prevent leggy growth. Keep soil consistently moist. Maintain humidity. Begin gentle air circulation once sprouted to prevent damping off.
Vegetative Growth
3-4 weeksPlants develop a compact, mounding shape with increasingly dense foliage. Bronze-tinted leaves multiply; plant fills out and branches proliferate.
Pinch back seedlings once or twice to encourage bushiness. Gradually acclimate to outdoor conditions if grown indoors. Maintain consistent moisture. Feed every 2 weeks with dilute balanced fertilizer.
Flowering
8-12 weeks or until frostAbundant small, delicate deep blue flowers appear at branch tips and continue throughout the season. Plant becomes completely covered with blooms in favorable conditions.
Deadhead spent flowers to encourage continuous blooming (though self-cleaning to some degree). Water consistently; drought stress halts flowering. Maintain moderate feeding. Provide afternoon shade in very hot climates.
End of Season
Variable; until frost or season endFlowering slows as temperatures cool in fall or during extreme heat in summer. Plant becomes less vigorous and may decline.
In cooler zones, plant will persist until first frost. In very hot climates, may need temporary shade or extra water to extend blooming. Deadhead to maximize late-season blooms.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
-
Spray with insecticidal soap or neem oil; encourage beneficial insects; isolate affected plants
-
Increase humidity and mist foliage; use miticide if severe; spray with water to dislodge
-
Spray with strong water stream; use insecticidal soap or neem oil; introduce ladybugs
-
and
Hand-pick in early morning or evening; use copper tape barriers; apply diatomaceous earth
Uses
Garden Edging and Borders
OrnamentalCrystal Palace Blue's compact, mounding habit makes it ideal for edging beds, creating crisp borders, and defining garden spaces. The dense cascade of blue flowers provides continuous color from early summer through fall. [source]
Container and Basket Planting
OrnamentalPerfect for hanging baskets, window boxes, and mixed containers where its trailing stems and profuse flowers cascade gracefully. The bronze foliage adds textural interest. [source]
Pollinator Attraction
WildlifeThe small flowers attract bees, butterflies, and other pollinators throughout the blooming season. Its extended flowering period supports beneficial insects during multiple life stages. [source]
Rock Garden and Alpine Planting
OrnamentalThe dwarf stature and dense growth habit make Crystal Palace Blue suitable for rock gardens, alpine troughs, and tight spaces where taller plants would be overwhelming. [source]
Harvest Tips
Lobelia is ornamental and not harvested for production, but deadheading spent flowers extends bloom time significantly. Pinch back 1/4 of foliage midsummer if plant becomes leggy to rejuvenate flowering.
Fun Facts
- 🌱 Crystal Palace Blue was named after the famous Victorian glass exhibition hall in London, reflecting its striking azure coloring.
- 🌱 Lobelia seeds are so tiny that a single gram contains approximately 15,000-20,000 seeds, making it extremely economical for gardeners.
- 🌱 The bronze foliage is characteristic of the Crystal Palace variety and intensifies with cooler temperatures and more sunlight exposure.
Gardening Terms
New to gardening? Learn about terms used in this guide:
Join 30,000 gardeners planning their gardens with LizPlants.
Get your personalized Crystal Palace Blue Lobelia planting timeline
Tell us your zip code and we'll calculate exactly when to start Crystal Palace Blue Lobelia seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.
Get my Crystal Palace Blue Lobelia timeline →