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Lobelia - Great Blue
Seed Packet

Lobelia - Great Blue

Lobelia siphilitica
Native to eastern areas, blue lobelia was named by Linnaeus, who had heard of its use by Native Americans to cure venereal disease. While false, the name stuck; however, it was used medicinally for colds and stomach troubles by Native people and colonists alike. The flowers cover the stout stems with bloom for over a month in late summer in moist soils. Lobelia attracts a wide array of beneficial insects and is one of the best choices for bumblebees.
SKU #S1276
Caution: Poisonous. The purchaser assumes all liability related to the use of this product.
$3.25
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Details
Approximate Seeds Per Packet
839
Lifecycle
Perennial
Perennial Hardiness Zone
4,
5,
6,
7,
8
Mature Size
2.5' h x 1.5' w
Sun
Full sun to partial shade
Soil
Rich, moist, well-drained
Season
Summer
Color
Spires of bright blue sometimes accented with purple
Features
Deer Resistant
Attracts Butterflies
Attracts Hummingbirds
Attracts Beneficial Insects
SOWING INSTRUCTIONS
Depth:
Surface sow; press into soil.
Sprout Time:
14-30 days after chill
Starting Indoors:
Recommended. Start indoors in late winter. Cover with a humidity dome or a light sprinkling of vermiculite to retain humidity until germination occurs. Keep at 70F. Alternately, while not essential, a cold, moist stratification period may increase germination. Sow in pots, cover with plastic, refrigerate at 36-40°F for 3-4 weeks, then bring into 70°F.
Starting Outdoors:
Not recommended, as seeds and new seedlings are very tiny and delicate. Possible to wintersow in late winter into pots placed in full shaded conditions and covered with a wire screen to keep out mice and voles. Check for water as needed.
WHEN TO SET OUTSIDE
At last frost date.
PLACEMENT & CULTIVATION
Lobelia was a horticultural prize brought from Canada to France in the early 1600s—Blue Cardinal was grown in early English gardens by 1665. A bee magnet that also attracts butterflies and their caterpillars, and supports beneficial insects, it grows best where soils are consistently moist, including water gardens and edges of streams and ponds, where it tolerates flooded conditions in spring. Add about an inch of mulch or compost to borders to help conserve moisture, keeping away from the plant's crown, and wait until spring to cut back. A short-lived perennial that can be renewed by seed or by dividing every 2-3 years in spring in zones 6 and in autumn in zones 7-9. Self-sows. Caution: toxic if ingested in significant amounts.
Final Spacing:
1.5'
Water Requirements:
Medium Water Use
Watering Details:
At least 1" per week. Keep evenly moist, but not soggy, allowing the soil to dry slightly between waterings.
Soil pH:
Most pH levels are tolerated.
Fertilizer:
Mix in 1-2" inches of compost prior to planting and top-dress with a thin layer each spring.
Diseases & Pests:
Lobelia can be susceptible to leaf spot and crown rot, but this can be avoided by placing in a location with plenty of air flow, watering mornings only and avoiding overly saturated soils. Slugs can occasionally be a problem, but can be treated by applying pelletized iron phosphate. Diatomaceous earth can also be used.
Growing Guides Winter Sowing Guide
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