Grow guide
How to grow Lobelia Great Blue
Lobelia siphilitica
- Type
- Lobelia
- Zones
- USDA zones 4–9
- Sun
- Partial
- Time to harvest
- 365–548 days
- Spacing
- 18″ apart
- Density
- 1 per sq ft
- Habit
- Upright
- Frost tolerance
- Hardy
- Sowing
- Start indoors, then transplant
- Start indoors
- 8 weeks before last frost
Care
- Water 2x/week in season
- Deadhead As needed
- Mulch Annual
Notes
Rich blue 3-4 ft spires bloom July-October in moist shade or part sun; surface-sow seeds needing light; self-seeds freely in wet soils.
More lobelia varieties
Grows well nearby
Track Lobelia Great Blue from seed to harvest with Evengrow.
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