Blog

When to Plant Snapdragon in Johnson County, NE

Johnson County, Nebraska Zone 5b August

August in the garden — Johnson County, Nebraska

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

Avg. last frost April 24
Avg. first frost October 7
Soil temp (4") 79°F
Watering High
Pest pressure High
Daylight 13.6 hrs
  1. It's harvest week for snapdragon

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

Coming up in September — start thinking about
  • First harvests: snapdragon

Instant PDF download. No spam, unsubscribe any time.

Snapdragons (Antirrhinum majus) are classic cool-season annuals whose upright spikes of dragon-lipped flowers are among spring's most dramatic displays. Tolerating light frosts, they bloom from early spring until summer heat shuts them down — then often revive in fall. In zones 9-11 they are grown as fall-planted winter annuals and may re-seed to naturalize.

Johnson County, Nebraska is in USDA Zone 5b. The average last spring frost is April 24 and the first fall frost is October 7, giving you a growing season of approximately 166 days.

At an elevation of 658 feet, Johnson County receives approximately 21.3 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Snapdragon during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting Fragrant
Johnson County, NE (Zone 5b) Moderate season
166 days
Last Spring Frost April 24
166 growing days
First Fall Frost October 7

Johnson County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.5

Drainage

Well Drained

Snapdragon Planting Risk Windows

Early Start (70% safe) ✓ Fits season (25 days to spare)
Start indoors: Feb 10 Transplant: Apr 21 🌸 Bloom: Jun 30 – Sep 8
Recommended (50%) ✓ Fits season (26 days to spare)
Start indoors: Feb 13 Transplant: Apr 24 🌸 Bloom: Jul 3 – Sep 11
Safe Start (90%) ✓ Fits season (24 days to spare)
Start indoors: Mar 2 Transplant: May 11 🌸 Bloom: Jul 20 – Sep 28

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 Johnson County

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

Soil pH

Your soil pH (6.3–7.5) overlaps with Snapdragon's range (6.2–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Snapdragon.

Organic Matter

Organic matter is moderate (3.4%). Annual compost additions will help Snapdragon.

How to Plant Snapdragon

9"
Between Plants
12"
Between Rows

Succession Planting Snapdragon

2
successive plantings in your 166-day season

Sow every 8 weeks. Last sowing by Jun 29 to harvest before frost.

Snapdragon Water Budget

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,349 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Snapdragon

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

Month Snapdragon Needs Rainfall You Supplement Action
Jan 0.5" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.4" 0" ❄️ Dormant
Apr 4.3" 1.9" 2.4" 🚿 Regular watering
May 4.3" 2.8" 1.5" 💧 Light watering
Jun 4.3" 3.3" 1" 💧 Light watering
Jul 4.3" 3" 1.3" 💧 Light watering
Aug 4.3" 2.6" 1.7" 💧 Light watering
Sep 4.3" 2.2" 2.1" 💧 Light 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 Johnson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Snapdragon 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.

Snapdragon needs ~1,232 GDD — county provides 2,407 GDD Excellent fit

Snapdragon Planting Timeline — Johnson County, NE

Snapdragon Planting Calendar

Activity When Date Range
Start Indoors February 13 Feb 13 – Feb 27
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 10 Apr 10 – May 1
Bloom July 3 Jul 3 – Sep 11

· 9" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6.2–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5b

📆 Growing Season

166 days in Johnson County

Growing Tips for Snapdragon in Johnson County

Direct sow Snapdragon outdoors after April 24 in Johnson County when soil has warmed and frost danger has passed.

Johnson County receives only 21" of rain annually. Snapdragon needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start indoors 10-12 weeks before last frost; seeds need light to germinate — press into moist medium and do not cover. Transplant after hardening off, even if light frosts remain. Pinch seedlings once to encourage branching. Deadhead to prolong blooming. In zones 8-11, sow in fall for a winter-to-spring show. Tall varieties (24-36") make excellent cut flowers.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Snapdragon in Johnson County, NE?

Johnson County is in Zone 5b with an average last frost of April 24. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, NE?

Johnson County, Nebraska is in USDA Hardiness Zone 5b. The average last spring frost is April 24 and first fall frost is October 7.

🌱

Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson 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.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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