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When to Plant Lobelia in Sequatchie County, TN

Sequatchie County, Tennessee Zone 7b June

Your June planting checklist for Sequatchie County, Tennessee

Here's what deserves your attention in Sequatchie County, Tennessee this month. Everything below is tailored to Zone 7b and timed around your local frost dates.

Avg. last frost April 6
Avg. first frost October 29
Soil temp (4") 67°F
Watering Low
Pest pressure High
Daylight 14.4 hrs
  1. Start lobelia under lights

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. Collect lobelia at their peak

    If you can't use it all right away, check the food-preservation section of your planner.

Before July arrives, get these ready
  • First harvests: 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.

Sequatchie County, Tennessee is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is October 29, giving you a growing season of approximately 206 days.

At an elevation of 3,890 feet, Sequatchie County receives approximately 52.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Lobelia during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lobelia root diseases.

Annual Blooms in Spring Pollinator-friendly
Sequatchie County, TN (Zone 7b) Long season
206 days
Last Spring Frost April 6
206 growing days
First Fall Frost October 29

Sequatchie County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.6

Drainage

Well Drained

Lobelia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (110 days to spare)
Start indoors: Jan 25 Transplant: Mar 1 🌸 Bloom: Apr 26 – Jul 5
Recommended (50%) ✓ Fits season (108 days to spare)
Start indoors: Feb 2 Transplant: Mar 9 🌸 Bloom: May 4 – Jul 13
Safe Start (90%) ✓ Fits season (109 days to spare)
Start indoors: Feb 15 Transplant: Mar 22 🌸 Bloom: May 17 – Jul 26

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 Sequatchie County

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

Soil pH

Your soil pH (5.7–6.6) overlaps with Lobelia's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Lobelia.

How to Plant Lobelia

6"
Between Plants
8"
Between Rows

Succession Planting Lobelia

3
successive plantings in your 206-day season

Sow every 8 weeks. Last sowing by Aug 10 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 5" 0" ❄️ Dormant
Feb 4.1" 0" ❄️ Dormant
Mar 4.4" 0" ❄️ Dormant
Apr 4.3" 4.3" 0" ✅ Rainfall sufficient
May 4.3" 4.6" 0" ✅ Rainfall sufficient
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 5.7" 0" ✅ Rainfall sufficient
Aug 4.3" 4.9" 0" ✅ Rainfall sufficient
Sep 4.3" 3.6" 0.7" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 4.4" 0" ❄️ Dormant
Dec 4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Sequatchie 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 ~1,256 GDD — county provides 3,450 GDD Excellent fit

Lobelia Planting Timeline — Sequatchie County, TN

Lobelia Planting Calendar

Activity When Date Range
Start Indoors February 2 Feb 2 – Feb 16
Transplant Outdoors March 9 Mar 9 – Mar 23
Bloom May 4 May 4 – Jul 13

· 6" apart · Rows 8" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Transplant Outdoors
April
May Bloom
June Bloom
July Bloom
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 7b

📆 Growing Season

206 days in Sequatchie County

Growing Tips for Lobelia in Sequatchie County

Direct sow Lobelia outdoors after April 06 in Sequatchie County when soil has warmed and frost danger has passed.

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 Sequatchie County, TN?

Sequatchie County is in Zone 7b with an average last frost of April 6. Plan your Lobelia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sequatchie County, TN?

Sequatchie County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is October 29.

🌱

Your Sequatchie County Garden Planner — Free

A 22-page printable planner built for Sequatchie County (Zone 7b). 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 Sequatchie County, TN. 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.