When to plant Snapdragon in Putnam County County,
In Putnam County County, plant Snapdragon in spring between April 7 and April 28, once soil temps hold above 50°F. Putnam County County's last frost averages April 21, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between and — roughly 100 days before the first frost on October 13.
When to Plant Snapdragon in Putnam County, IL
June in the garden — Putnam County, Illinois
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Putnam County, Illinois.
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Sow snapdragon in trays indoors
These need a head start before your last frost (April 21). Sow into cells now so you're ready to transplant in a few weeks.
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Collect snapdragon at their peak
If you can't use it all right away, check the food-preservation section of your planner.
A few tasks this June that'll pay off in July
- First harvests: snapdragon
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.
Putnam County, Illinois is in USDA Zone 5b. The average last spring frost is April 21 and the first fall frost is October 13, giving you a growing season of approximately 175 days.
At an elevation of 582 feet, Putnam County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Snapdragon during the growing season.
Putnam County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.7
Drainage
Well Drained
Snapdragon Planting Risk Windows
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 Putnam County
How your county's soil matches Snapdragon's growing requirements.
Soil pH
Your soil pH (6.0–6.7) overlaps with Snapdragon's range (6.2–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Putnam County is excellent for Snapdragon — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Snapdragon.
Organic Matter
Organic matter is excellent (4.3%) — Snapdragon will thrive.
How to Plant Snapdragon
Succession Planting Snapdragon
Sow every 8 weeks. Last sowing by Jul 05 to harvest before frost.
Snapdragon Water Budget
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 | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 2" | 0" | ❄️ Dormant |
| Mar | — | 3.1" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| May | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.3" | 1" | 💧 Light watering |
| Oct | 4.3" | 3.3" | 1" | 💧 Light watering |
| Nov | — | 3.2" | 0" | ❄️ Dormant |
| Dec | — | 2.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Putnam 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 Planting Timeline — Putnam County, IL
Snapdragon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 10 | Feb 10 – Feb 24 |
| Transplant Outdoors | April 21 | Apr 21 – May 5 |
| Direct Sow | April 7 | Apr 7 – Apr 28 |
| Bloom | June 30 | Jun 30 – Sep 8 |
· 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Bloom |
| 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 5b
📆 Growing Season
175 days in Putnam County
Growing Tips for Snapdragon in Putnam County
Direct sow Snapdragon outdoors after April 21 in Putnam 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 →
Snapdragon in Other Locations
Frequently Asked Questions
When should I plant Snapdragon in Putnam County, IL?
Putnam County is in Zone 5b with an average last frost of April 21. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Putnam County, IL?
Putnam County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 21 and first fall frost is October 13.
When should I plant Snapdragon in Putnam County, ?
In Putnam County, , plant Snapdragon after the last frost (around April 21) and before the first frost (around October 13). Best results when soil holds above 50°F.
What growing zone is Putnam County, for Snapdragon?
Putnam County sits in USDA Zone 5b. Snapdragon grows reliably in zones 2a through 11b, so it's a good fit here.
Can Snapdragon grow in Putnam County's climate?
Yes — Snapdragon grows well in Putnam County's temperate climate. Putnam County averages a 175-day frost-free season, with last frost around April 21 and first frost around October 13.
Your Putnam County Garden Planner — Free
A 22-page printable planner built for Putnam 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.