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When to plant Lobelia in Lamar County County,

Lamar County County sits in cold Zone 8a. Plant Lobelia February 16–March 2 for the single annual harvest; the November 6 first frost closes the window.

When to Plant Lobelia in Lamar County, AL

Lamar County, Alabama Zone 8a June

June in the garden — Lamar County, Alabama

Each item below is timed to Lamar County, Alabama's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost March 23
Avg. first frost November 6
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 14.2 hrs
  1. Basket week: lobelia

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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.

Lamar County, Alabama is in USDA Zone 8a. The average last spring frost is March 23 and the first fall frost is November 6, giving you a growing season of approximately 228 days.

At an elevation of 69 feet, Lamar County receives approximately 62 inches of rainfall annually with predominantly clay loam soil. Summer highs average 88°F, providing good warmth for Lobelia during the growing season. Clay soil retains moisture well for Lobelia, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lobelia root diseases.

Annual Blooms in Spring Pollinator-friendly
Lamar County, AL (Zone 8a) Long season
228 days
Last Spring Frost March 23
228 growing days
First Fall Frost November 6

Lamar County Soil Profile

Soil Type

Clay Loam

Soil pH

5.3-6.7

Drainage

Well Drained

Lobelia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (151 days to spare)
Start indoors: Jan 17 Transplant: Feb 7 🌸 Bloom: Apr 4 – May 30
Recommended (50%) ✓ Fits season (151 days to spare)
Start indoors: Jan 26 Transplant: Feb 16 🌸 Bloom: Apr 13 – Jun 8
Safe Start (90%) ✓ Fits season (150 days to spare)
Start indoors: Feb 16 Transplant: Mar 9 🌸 Bloom: May 4 – Jun 29

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Lamar County

How your county's soil matches Lobelia's growing requirements.

Soil pH

Your soil pH (5.3–6.7) overlaps with Lobelia's range (6.0–7.0), though not a perfect match.

Soil Texture

The clay loam soil in Lamar County is excellent for Lobelia — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Lobelia.

How to Plant Lobelia

6"
Between Plants
8"
Between Rows

Succession Planting Lobelia

3
successive plantings in your 228-day season

Sow every 8 weeks. Last sowing by Aug 18 to harvest before frost.

Lobelia Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Lobelia

Lobelia needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Lobelia Needs Rainfall You Supplement Action
Jan 4.7" 0" ❄️ Dormant
Feb 4.6" 0" ❄️ Dormant
Mar 4.3" 6.8" 0" ✅ Rainfall sufficient
Apr 4.3" 4.2" 0.1" 💧 Light watering
May 4.3" 5.3" 0" ✅ Rainfall sufficient
Jun 4.3" 5.9" 0" ✅ Rainfall sufficient
Jul 4.3" 5.8" 0" ✅ Rainfall sufficient
Aug 4.3" 6.8" 0" ✅ Rainfall sufficient
Sep 4.3" 5" 0" ✅ Rainfall sufficient
Oct 4.3" 4.1" 0.2" 💧 Light watering
Nov 4.3" 4.6" 0" ✅ Rainfall sufficient
Dec 4.4" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Lamar County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Lobelia Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Lobelia needs ~1,200 GDD — county provides 3,648 GDD Excellent fit

Lobelia Planting Timeline — Lamar County, AL

Lobelia Planting Calendar

Activity When Date Range
Start Indoors January 26 Jan 26 – Feb 9
Transplant Outdoors February 16 Feb 16 – Mar 2
Bloom April 13 Apr 13 – Jun 8

· 6" apart · Rows 8" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

70–80 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

228 days in Lamar County

Growing Tips for Lobelia in Lamar County

Direct sow Lobelia outdoors after March 23 in Lamar County when soil has warmed and frost danger has passed.

With Lamar County's clay soil (28% clay), work in 3-4 inches of compost before planting Lobelia. Avoid tilling when soil is wet to prevent compaction.

General growing tips

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 Lamar County, AL?

Lamar County is in Zone 8a with an average last frost of March 23. Plan your Lobelia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lamar County, AL?

Lamar County, Alabama is in USDA Hardiness Zone 8a. The average last spring frost is March 23 and first fall frost is November 6.

When should I plant Lobelia in Lamar County County, ?

In Lamar County County, , plant Lobelia after the last frost (around March 23) and before the first frost (around November 6). Best results when soil holds above 50°F.

What growing zone is Lamar County County, for Lobelia?

Lamar County County sits in USDA Zone 8a. Lobelia grows reliably in zones 3a through 9b, so it's a good fit here.

Can Lobelia grow in Lamar County County's climate?

Yes — Lobelia grows well in Lamar County County's temperate climate. Lamar County County averages a 228-day frost-free season, with last frost around March 23 and first frost around November 6.

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A 22-page printable planner built for Lamar County (Zone 8a). 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 Lamar County, AL. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.