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When to plant Snapdragon in Cooper County, MO

Spring Snapdragon in Cooper County goes in March 20–April 10, once nighttime temps stop dipping near freezing.

When to Plant Snapdragon in Cooper County, MO

Cooper County, Missouri Zone 6b July

July in Cooper County, Missouri — your action list

July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Cooper County, Missouri.

Avg. last frost April 10
Avg. first frost October 25
Soil temp (4") 82°F
Watering Low
Pest pressure High
Daylight 14.5 hrs
  1. Start harvesting snapdragon

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Coming up in August — start thinking about
  • 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.

Cooper County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 25, giving you a growing season of approximately 198 days.

At an elevation of 1,035 feet, Cooper County receives approximately 35.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Snapdragon during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting Fragrant
Cooper County, MO (Zone 6b) Moderate season
198 days
Last Spring Frost April 10
198 growing days
First Fall Frost October 25

Cooper County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.7

Drainage

Well Drained

Snapdragon Planting Risk Windows

Early Start (70% safe) ✓ Fits season (49 days to spare)
Start indoors: Jan 24 Transplant: Apr 4 🌸 Bloom: Jun 13 – Aug 29
Recommended (50%) ✓ Fits season (51 days to spare)
Start indoors: Jan 30 Transplant: Apr 10 🌸 Bloom: Jun 19 – Sep 4
Safe Start (90%) ✓ Fits season (49 days to spare)
Start indoors: Feb 13 Transplant: Apr 24 🌸 Bloom: Jul 3 – Sep 18

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 Cooper County

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

Soil pH

Your soil pH (5.4–6.7) is more acidic than Snapdragon prefers (6.2–7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Snapdragon.

How to Plant Snapdragon

9"
Between Plants
12"
Between Rows

Succession Planting Snapdragon

3
successive plantings in your 198-day season

Sow every 8 weeks. Last sowing by Jul 17 to harvest before frost.

Snapdragon 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 420 gal / 100 sq ft

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 1.4" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3" 1.3" 💧 Light watering
May 4.3" 4.4" 0" ✅ Rainfall sufficient
Jun 4.3" 5.1" 0" ✅ Rainfall sufficient
Jul 4.3" 4.3" 0" ✅ Rainfall sufficient
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 3" 1.3" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Cooper 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 ~1,360 GDD — county provides 3,168 GDD Excellent fit

Snapdragon Planting Timeline — Cooper County, MO

Snapdragon Planting Calendar

Activity When Date Range
Start Indoors January 30 Jan 30 – Feb 13
Transplant Outdoors April 10 Apr 10 – Apr 24
Direct Sow March 20 Mar 20 – Apr 10
Bloom June 19 Jun 19 – Sep 4

· 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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6.2–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 6b

📆 Growing Season

198 days in Cooper County

Growing Tips for Snapdragon in Cooper County

Direct sow Snapdragon outdoors after April 10 in Cooper 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 Cooper County, MO?

Cooper County is in Zone 6b with an average last frost of April 10. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cooper County, MO?

Cooper County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 25.

When should I plant Snapdragon in Cooper County, MO?

In Cooper County, MO, plant Snapdragon after the last frost (around April 10) and before the first frost (around October 25). Best results when soil holds above 50°F.

What growing zone is Cooper County, MO for Snapdragon?

Cooper 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 Cooper County's climate?

Yes — Snapdragon grows well in Cooper County's temperate climate. Cooper County averages a 198-day frost-free season, with last frost around April 10 and first frost around October 25.

🌱

Your Cooper County Garden Planner — Free

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

Sources & credits

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