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When to Plant Lobelia in Frontier County, NE

Lobelia (Lobelia erinus) is a cool-season annual prized for the intense cobalt blue that is rare among bedding flowers. It blooms most prolifically in spring and early summer but stalls or dies back during heat peaks above 90°F. In zones 3–7 it delivers a long display; in zones 8–9 it is best treated as a spring annual that fades by midsummer. Trailing types cascade beautifully from containers and window boxes.

Frontier County, Nebraska is in USDA Zone 5b. The average last spring frost is May 2 and the first fall frost is October 6, giving you a growing season of approximately 157 days.

At an elevation of 1,066 feet, Frontier County receives approximately 34.6 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Lobelia to ensure they mature before fall.

Annual Blooms in Spring Pollinator-friendly
Frontier County, NE (Zone 5b) Moderate season
157 days
Last Spring Frost May 2
157 growing days
First Fall Frost October 6

Frontier County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Lobelia Planting Timeline — Frontier County, NE

Lobelia Planting Calendar

Activity When Date Range
Start Indoors February 21 Feb 21 – Mar 7
Transplant Outdoors April 25 Apr 25 – May 9
Bloom June 20 Jun 20 – Sep 5

· 6" apart · Rows 8" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April Transplant Outdoors
May Transplant Outdoors
June Bloom
July Bloom
August Bloom
September Bloom
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

70–80 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

157 days in Frontier County

Growing Tips for Frontier County

Start seeds indoors 10–12 weeks before last frost — seed is dust-fine and requires light to germinate; surface-sow and press gently. Keep at 65–70°F. Not reliably direct-sown. Transplant in cool weather, 2–4 weeks before last frost date is acceptable in zones 5+. Shear plants by one-third after the first bloom flush to encourage a second flush in fall. Provide afternoon shade in zones 7+ to extend bloom into summer.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lobelia in Frontier County, NE?

Frontier County is in Zone 5b with an average last frost of May 2. Plan your Lobelia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Frontier County, NE?

Frontier County, Nebraska is in USDA Hardiness Zone 5b. The average last spring frost is May 2 and first fall frost is October 6.

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Your Frontier County Garden Planner — Free

A 22-page printable planner built for Frontier County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Frontier County, NE. Local conditions may vary. Last updated: June 2026.

Sources & credits

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