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When to plant Snapdragon in Johnson County County,

Plant Snapdragon in Johnson County County, when soil hits 50°F — usually March 18. Continue planting through April 8 for the spring crop.

When to Plant Snapdragon in Johnson County, KS

Johnson County, Kansas Zone 6b June

Your June game plan for Johnson County, Kansas

Your garden in Johnson County, Kansas is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost April 8
Avg. first frost October 26
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 14.7 hrs
  1. Start snapdragon under lights

    You're about 19 weeks out from your last frost — the perfect window to get these germinating indoors.

  2. Collect snapdragon at their peak

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

July will be here before you know it — start on
  • First harvests: snapdragon

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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, Kansas is in USDA Zone 6b. The average last spring frost is April 8 and the first fall frost is October 26, giving you a growing season of approximately 201 days.

At an elevation of 768 feet, Johnson County receives approximately 27.6 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Snapdragon during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting Fragrant
Johnson County, KS (Zone 6b) Long season
201 days
Last Spring Frost April 8
201 growing days
First Fall Frost October 26
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Johnson County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.2

Drainage

Well Drained

Snapdragon Planting Risk Windows

Early Start (70% safe) ✓ Fits season (54 days to spare)
Start indoors: Jan 24 Transplant: Apr 4 🌸 Bloom: Jun 13 – Aug 29
Recommended (50%) ✓ Fits season (54 days to spare)
Start indoors: Jan 28 Transplant: Apr 8 🌸 Bloom: Jun 17 – Sep 2
Safe Start (90%) ✓ Fits season (58 days to spare)
Start indoors: Feb 12 Transplant: Apr 23 🌸 Bloom: Jul 2 – Sep 17

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 (6.8–7.2) 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.

Organic Matter

Organic matter is excellent (4.2%) — Snapdragon will thrive.

How to Plant Snapdragon

9"
Between Plants
12"
Between Rows

Succession Planting Snapdragon

3
successive plantings in your 201-day season

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

Snapdragon 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 909 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 0.8" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 4.1" 0.2" 💧 Light watering
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 2.3" 2" 💧 Light watering
Oct 4.3" 1.8" 2.5" 🚿 Regular watering
Nov 1" 0" ❄️ Dormant
Dec 0.7" 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 ~1,296 GDD — county provides 3,065 GDD Excellent fit

Snapdragon Planting Timeline — Johnson County, KS

Snapdragon Planting Calendar

Activity When Date Range
Start Indoors January 28 Jan 28 – Feb 11
Transplant Outdoors April 8 Apr 8 – Apr 22
Direct Sow March 18 Mar 18 – Apr 8
Bloom June 17 Jun 17 – Sep 2

· 9" apart · Rows 12" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6.2–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

201 days in Johnson County

Growing Tips for Snapdragon in Johnson County

Direct sow Snapdragon outdoors after April 08 in Johnson County when soil has warmed and frost danger has passed.

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, KS?

Johnson County is in Zone 6b with an average last frost of April 8. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, KS?

Johnson County, Kansas is in USDA Hardiness Zone 6b. The average last spring frost is April 8 and first fall frost is October 26.

When should I plant Snapdragon in Johnson County, ?

In Johnson County, , plant Snapdragon after the last frost (around April 8) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Johnson County, for Snapdragon?

Johnson County sits in USDA Zone 6b. Snapdragon grows reliably in zones 2a through 11b, so it's a good fit here.

Can Snapdragon grow in Johnson County's climate?

Yes — Snapdragon grows well in Johnson County's temperate climate. Johnson County averages a 201-day frost-free season, with last frost around April 8 and first frost around October 26.

🌱

Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson County (Zone 6b). 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 Johnson County, KS. 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.