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When to plant Snapdragon in Glenn County County,

Glenn County County sits in USDA Zone 9b. Plant Snapdragon between January 2 (after last frost on March 6) and January 23. A second sowing from September 5 to September 19 extends the harvest into fall.

When to Plant Snapdragon in Glenn County, CA

Glenn County, California Zone 9b June

June in Glenn County, California — your action list

Welcome to June in Zone 9b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost March 6
Avg. first frost November 28
Soil temp (4") 85°F
Watering Critical
Pest pressure High
Daylight 14.8 hrs
  1. Pick snapdragon

    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.

Glenn County, California is in USDA Zone 9b. The average last spring frost is March 6 and the first fall frost is November 28, giving you a growing season of approximately 267 days.

At an elevation of 270 feet, Glenn County receives approximately 27.1 inches of rainfall annually with predominantly 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
Glenn County, CA (Zone 9b) Long season
267 days
Last Spring Frost March 6
267 growing days
First Fall Frost November 28
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Glenn County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.9

Drainage

Well Drained

Snapdragon Planting Risk Windows

Early Start (70% safe) ✓ Fits season (109 days to spare)
Transplant: Jan 19 🌸 Bloom: Mar 23 – Aug 3
Recommended (50%) ✓ Fits season (106 days to spare)
Transplant: Jan 30 🌸 Bloom: Apr 3 – Aug 14
Safe Start (90%) ✓ Fits season (84 days to spare)
Transplant: Mar 14 🌸 Bloom: May 16 – Sep 26

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 Glenn County

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

Soil pH

Your soil pH (6.5–7.9) is more alkaline than Snapdragon prefers (6.2–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Snapdragon.

How to Plant Snapdragon

9"
Between Plants
12"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Snapdragon

4
successive plantings in your 267-day season

Sow every 8 weeks. Last sowing by Aug 20 to harvest before frost.

For a dedicated fall crop, sow by Sep 05.

Snapdragon Water Budget

Plant needs
1.0″/week
Rainfall provides
0.4″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,636 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 5.6" 0" ❄️ Dormant
Feb 5.3" 0" ❄️ Dormant
Mar 4.3" 4.4" 0" ✅ Rainfall sufficient
Apr 4.3" 2.5" 1.8" 💧 Light watering
May 4.3" 0.7" 3.6" 🚿 Regular watering
Jun 4.3" 0.1" 4.2" 🚿 Regular watering
Jul 4.3" 0" 4.3" 🚿 Regular watering
Aug 4.3" 0" 4.3" 🚿 Regular watering
Sep 4.3" 0.3" 4" 🚿 Regular watering
Oct 4.3" 1.3" 3" 🚿 Regular watering
Nov 4.3" 2.5" 1.8" 💧 Light watering
Dec 4.3" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Glenn 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 4,272 GDD Excellent fit

Snapdragon Planting Timeline — Glenn County, CA

Snapdragon Planting Calendar

Activity When Date Range
Transplant Outdoors January 30 Jan 30 – Feb 13
Direct Sow January 2 Jan 2 – Jan 23
Bloom April 3 Apr 3 – Aug 14
Fall Sowing September 5 Sep 5 – Sep 19

· 9" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Transplant Outdoors Direct Sow
February Transplant Outdoors
March
April Bloom
May Bloom
June Bloom
July Bloom
August Bloom
September Fall Sowing
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: too_alkaline

🗺️ USDA Zone

Zone 9b

📆 Growing Season

267 days in Glenn County

Growing Tips for Snapdragon in Glenn County

Direct sow Snapdragon outdoors after March 06 in Glenn 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 Glenn County, CA?

Glenn County is in Zone 9b with an average last frost of March 6. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Glenn County, CA?

Glenn County, California is in USDA Hardiness Zone 9b. The average last spring frost is March 6 and first fall frost is November 28.

When should I plant Snapdragon in Glenn County County, ?

In Glenn County County, , plant Snapdragon after the last frost (around March 6) and before the first frost (around November 28). Best results when soil holds above 50°F.

What growing zone is Glenn County County, for Snapdragon?

Glenn County County sits in USDA Zone 9b. Snapdragon grows reliably in zones 2a through 11b, so it's a good fit here.

Can Snapdragon grow in Glenn County County's climate?

Yes — Snapdragon grows well in Glenn County County's temperate climate. Glenn County County averages a 267-day frost-free season, with last frost around March 6 and first frost around November 28.

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Your Glenn County Garden Planner — Free

A 22-page printable planner built for Glenn County (Zone 9b). 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 Glenn County, CA. 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.