Crystal Palace Lobelia is a half-hardy annual that rewards gardeners with brilliant violet-blue blooms from spring through summer. This compact cultivar reaches just 4-6 inches tall and flowers in 80-89 days, making it quick enough to fill gaps in borders or containers. Hardy in zones 4-9, it thrives in full sun and prefers neutral soil (pH 6.0-7.0). The flowers are classically petite, around half an inch across, and create an almost cloud-like effect when planted en masse, earning this variety its reputation as a proven garden performer.
Photo © True Leaf Market
Growing Conditions
USDA Zone
4-9
Sunlight
Full Sun
Soil
Well-drained, Fertile Loam; Moist But Not Waterlogged
Preferred Temp60-75°F
Growth Stats
6 in
Height
—
Width
6 in
Spacing
80–89
Days to Harvest
PeriodAnnual
TypeBush
Plant Profile
Sunlight
Full Sun
Water
—
Zones
4-9
Size
6in H x ?in W
Growth
Annual
Care
High
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Highlights
Those half-inch violet-blue flowers arrive reliably and profusely, creating a jewel-toned carpet that works equally well indoors under grow lights or in garden beds alongside daisies and pansies. Its compact bush form means you don't need much space, and it germinates quickly at 60-70°F, so you can have transplants ready within weeks of starting seed. The real appeal lies in its dual nature: equally celebrated as a greenhouse specimen and a garden workhorse, it bridges the gap between tender ornamental and rugged performer.
Common Uses
Crystal Palace Lobelia serves as a decorative flowering plant in garden borders, window boxes, and container plantings. Its cascading, compact growth and abundant blooms make it a natural choice for edging beds, filling in front-of-border spaces, and creating continuous color displays throughout the growing season.
Growing Timeline
First Bloom
Late Spring
First Harvest
N/a
Last Harvest
N/a
Care Instructions
Start Indoors
Start seeds indoors 8-10 weeks before your average last frost date. Maintain soil temperature at 60-70°F for optimal germination. Press seeds lightly into the surface; they require light to germinate and should not be covered with soil.
Transplant Outdoors
Transplant seedlings outdoors 1-2 weeks after your average last frost date once they have developed true leaves. Space plants 6 inches apart in rows 18 inches apart. Harden off seedlings gradually before transplanting to acclimate them to outdoor conditions.
Direct Sow
Direct sow seeds 1-2 weeks after your average last frost date, pressing them lightly into the soil surface. In mild climates, sow in late summer for winter color.
Pruning
No formal pruning is necessary, though deadheading spent flowers will encourage continuous blooming throughout the season.
Growing Calendar
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Companion Planting
Ecology & Traits
Scientific Classification
Lobelia L.
Family
Campanulaceae
Genus
Lobelia
Duration
Annual
Growth Habit
Bush
Native Status
L48 (I)HI (I)