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When to Plant Lobelia in Huron County, OH

Huron County, Ohio Zone 6a July

July in Huron County, Ohio — your action list

Your Huron County, Ohio garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.

Avg. last frost April 27
Avg. first frost October 18
Soil temp (4") 76°F
Watering Moderate
Pest pressure High
Daylight 14.7 hrs
  1. It's harvest week for lobelia

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

Get ahead of August
  • 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.

Huron County, Ohio is in USDA Zone 6a. The average last spring frost is April 27 and the first fall frost is October 18, giving you a growing season of approximately 174 days.

At an elevation of 1,242 feet, Huron County receives approximately 32.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Lobelia during the growing season.

Annual Blooms in Spring Pollinator-friendly
Huron County, OH (Zone 6a) Moderate season
174 days
Last Spring Frost April 27
174 growing days
First Fall Frost October 18

Huron County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7.1

Drainage

Well Drained

Lobelia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (46 days to spare)
Start indoors: Feb 19 Transplant: Apr 9 🌸 Bloom: Jun 4 – Aug 27
Recommended (50%) ✓ Fits season (48 days to spare)
Start indoors: Feb 23 Transplant: Apr 13 🌸 Bloom: Jun 8 – Aug 31
Safe Start (90%) ✓ Fits season (45 days to spare)
Start indoors: Mar 11 Transplant: Apr 29 🌸 Bloom: Jun 24 – Sep 16

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 Huron County

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

Soil pH

Your soil pH (6.1–7.1) overlaps with Lobelia's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (4.0%). Annual compost additions will help Lobelia.

How to Plant Lobelia

6"
Between Plants
8"
Between Rows

Succession Planting Lobelia

2
successive plantings in your 174-day season

Sow every 8 weeks. Last sowing by Jul 30 to harvest before frost.

Lobelia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 326 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 1.4" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 4.3" 3.5" 0.8" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 3.6" 0.7" 💧 Light watering
Aug 4.3" 3" 1.3" 💧 Light watering
Sep 4.3" 2.5" 1.8" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Huron 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 ~1,144 GDD — county provides 2,653 GDD Excellent fit

Lobelia Planting Timeline — Huron County, OH

Lobelia Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors April 13 Apr 13 – Apr 27
Bloom June 8 Jun 8 – Aug 31

· 6" apart · Rows 8" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–80 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

174 days in Huron County

Growing Tips for Lobelia in Huron County

Direct sow Lobelia outdoors after April 27 in Huron 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 Huron County, OH?

Huron County is in Zone 6a with an average last frost of April 27. Plan your Lobelia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Huron County, OH?

Huron County, Ohio is in USDA Hardiness Zone 6a. The average last spring frost is April 27 and first fall frost is October 18.

🌱

Your Huron County Garden Planner — Free

A 22-page printable planner built for Huron County (Zone 6a). 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 Huron County, OH. Local conditions may vary. Last updated: July 2026.

Sources & credits

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