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When to Plant Snapdragon in Washington County, OH

Washington County, Ohio Zone 6b June

Top priorities for Washington County, Ohio gardeners in June

Here's what deserves your attention in Washington County, Ohio this month. Everything below is tailored to Zone 6b and timed around your local frost dates.

Avg. last frost April 28
Avg. first frost October 19
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
Get ahead of July
  • Starting indoors: snapdragon
  • 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.

Washington County, Ohio is in USDA Zone 6b. The average last spring frost is April 28 and the first fall frost is October 19, giving you a growing season of approximately 174 days.

At an elevation of 803 feet, Washington County receives approximately 30.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Snapdragon during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting Fragrant
Washington County, OH (Zone 6b) Moderate season
174 days
Last Spring Frost April 28
174 growing days
First Fall Frost October 19

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Snapdragon Planting Risk Windows

Early Start (70% safe) ✓ Fits season (30 days to spare)
Start indoors: Feb 10 Transplant: Apr 21 🌸 Bloom: Jun 30 – Sep 15
Recommended (50%) ✓ Fits season (27 days to spare)
Start indoors: Feb 17 Transplant: Apr 28 🌸 Bloom: Jul 7 – Sep 22
Safe Start (90%) ✓ Fits season (21 days to spare)
Start indoors: Mar 9 Transplant: May 18 🌸 Bloom: Jul 27 – Oct 12

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 Washington County

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

Soil pH

Your soil pH (5.7–6.7) overlaps with Snapdragon's range (6.2–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.1%) — Snapdragon will thrive.

How to Plant Snapdragon

9"
Between Plants
12"
Between Rows

Succession Planting Snapdragon

2
successive plantings in your 174-day season

Sow every 8 weeks. Last sowing by Jul 11 to harvest before frost.

Snapdragon Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 472 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 1.1" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 3.4" 0.9" 💧 Light watering
Aug 4.3" 3.1" 1.2" 💧 Light watering
Sep 4.3" 2.8" 1.5" 💧 Light watering
Oct 4.3" 2.3" 2" 💧 Light watering
Nov 2.1" 0" ❄️ Dormant
Dec 1.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Washington 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 ~1,424 GDD — county provides 2,914 GDD Excellent fit

Snapdragon Planting Timeline — Washington County, OH

Snapdragon Planting Calendar

Activity When Date Range
Start Indoors February 17 Feb 17 – Mar 3
Transplant Outdoors April 28 Apr 28 – May 12
Direct Sow April 7 Apr 7 – Apr 28
Bloom July 7 Jul 7 – Sep 22

· 9" apart · Rows 12" apart

Month-by-Month Timeline

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

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

174 days in Washington County

Growing Tips for Snapdragon in Washington County

Direct sow Snapdragon outdoors after April 28 in Washington 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 Washington County, OH?

Washington County is in Zone 6b with an average last frost of April 28. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washington County, OH?

Washington County, Ohio is in USDA Hardiness Zone 6b. The average last spring frost is April 28 and first fall frost is October 19.

🌱

Your Washington County Garden Planner — Free

A 22-page printable planner built for Washington 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 Washington County, OH. 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.