How to grow Great Blue Lobelia

Lobelia siphilitica

Partial Sun
OR
Full Sun
High

Great hardy plant for rain gardens or other moist areas. Lovely blue-purple flowers attract bees and other pollinators. Can be a short-lived perennial; may spread seed enthusiastically.

Reportedly planting it in a shadier area will give more intensely-colored blooms.

Growing Great Blue Lobelia from seed

Cold stratification / winter sowing is helpful.

By our calculations*, you should look at sowing Great Blue Lobelia about 105 days before your last frost date .

Transplanting Great Blue Lobelia

Native habitat – often found near or on stream banks.

Ensure that temperatures are mild and all chance of frost has passed before planting out, as Great Blue Lobelia is a very hardy plant.

Seed Saving Great Blue Lobelia

Allow pods to dry on plant, then collect. Or just shake the plant around to distribute seeds nearby.

How long does Great Blue Lobelia take to grow?

These estimates for how long Great Blue Lobelia takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.

Days to Germination How long does it take Great Blue Lobelia to germinate?: 20 days
Average 20 days | Min 6 days | Max 88 days (9)
Days to Transplant How long until I can plant out Great Blue Lobelia?: + 96 days
Average 96 days | Min 65 days | Max 160 days (4)
Days to Maturity How long until Great Blue Lobelia is ready for harvest / bloom?: + days
Average days | Min days | Max days (0)
Total Growing Days How long does it take to grow Great Blue Lobelia?: = days

When should I plant Great Blue Lobelia?

Our when to plant Great Blue Lobelia estimates are relative to your last frost date.

When to sow The number of days to sow Great Blue Lobelia before or after your last frost date.: 105 days before Last Frost Date

Great Blue Lobelia Etymology

The name, siphilitica, comes from the fact that it was a used as cure for syphilis.¹²

Other names for Great Blue Lobelia

Great blue lobelia

Lobelia siphilitica L.

Footnotes

¹ Lady Bird Johnson Wildflower Center

² Missouri Botanical Garden