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When to Plant Lobelia in Saunders County, NE

Saunders County, Nebraska Zone 5b July

This month in Saunders County, Nebraska

July is a pivotal month for Saunders County, Nebraska gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 22
Avg. first frost October 11
Soil temp (4") 79°F
Watering Moderate
Pest pressure High
Daylight 14.7 hrs
  1. Start lobelia indoors

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Harvest lobelia as they ripen

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

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.

Saunders County, Nebraska is in USDA Zone 5b. The average last spring frost is April 22 and the first fall frost is October 11, giving you a growing season of approximately 172 days.

At an elevation of 705 feet, Saunders County receives approximately 22.5 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Lobelia during the growing season.

Annual Blooms in Spring Pollinator-friendly
Saunders County, NE (Zone 5b) Moderate season
172 days
Last Spring Frost April 22
172 growing days
First Fall Frost October 11

Saunders County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.5

Drainage

Well Drained

Lobelia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (46 days to spare)
Start indoors: Feb 6 Transplant: Apr 10 🌸 Bloom: Jun 5 – Aug 21
Recommended (50%) ✓ Fits season (46 days to spare)
Start indoors: Feb 11 Transplant: Apr 15 🌸 Bloom: Jun 10 – Aug 26
Safe Start (90%) ✓ Fits season (43 days to spare)
Start indoors: Feb 27 Transplant: May 1 🌸 Bloom: Jun 26 – Sep 11

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 Saunders County

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

Soil pH

Your soil pH (6.6–7.5) is more alkaline than Lobelia prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Lobelia.

How to Plant Lobelia

6"
Between Plants
8"
Between Rows

Succession Planting Lobelia

2
successive plantings in your 172-day season

Sow every 8 weeks. Last sowing by Jul 23 to harvest before frost.

Lobelia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 828 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 0.6" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 4.3" 2.6" 1.7" 💧 Light watering
May 4.3" 3" 1.3" 💧 Light watering
Jun 4.3" 3.7" 0.6" 💧 Light watering
Jul 4.3" 3.1" 1.2" 💧 Light watering
Aug 4.3" 2.5" 1.8" 💧 Light watering
Sep 4.3" 2" 2.3" 🚿 Regular watering
Oct 4.3" 1.5" 2.8" 🚿 Regular watering
Nov 0.8" 0" ❄️ Dormant
Dec 0.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Saunders 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 2,623 GDD Excellent fit

Lobelia Planting Timeline — Saunders County, NE

Lobelia Planting Calendar

Activity When Date Range
Start Indoors February 11 Feb 11 – Feb 25
Transplant Outdoors April 15 Apr 15 – Apr 29
Bloom June 10 Jun 10 – Aug 26

· 6" apart · Rows 8" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March
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 · 1-2 times/week

📅 Days to Maturity

70–80 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

172 days in Saunders County

Growing Tips for Lobelia in Saunders County

Direct sow Lobelia outdoors after April 22 in Saunders County when soil has warmed and frost danger has passed.

Saunders County receives only 22" of rain annually. Lobelia needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 Saunders County, NE?

Saunders County is in Zone 5b with an average last frost of April 22. Plan your Lobelia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Saunders County, NE?

Saunders County, Nebraska is in USDA Hardiness Zone 5b. The average last spring frost is April 22 and first fall frost is October 11.

🌱

Your Saunders County Garden Planner — Free

A 22-page printable planner built for Saunders 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 Saunders County, NE. Local conditions may vary. Last updated: July 2026.

Sources & credits

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