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When to plant Sweet Pea in Edwards County, IL

Spring Sweet Pea in Edwards County goes in March 5–March 26, once nighttime temps stop dipping near freezing.

When to Plant Sweet Pea in Edwards County, IL

Edwards County, Illinois Zone 6b July

Your July gardening checklist

Welcome to July in Zone 6b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 9
Avg. first frost October 28
Soil temp (4") 80°F
Watering Low
Pest pressure High
Daylight 14.4 hrs

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Sweet peas (Lathyrus odoratus) are beloved cool-season climbing annuals grown primarily for their intensely fragrant, ruffled blooms in shades of pink, purple, red, and white. They thrive in cool spring conditions, climbing trellises to 4–6 feet, and make outstanding cut flowers. Bloom ceases once summer heat arrives, making early sowing critical for a long cutting season.

Edwards County, Illinois is in USDA Zone 6b. The average last spring frost is April 9 and the first fall frost is October 28, giving you a growing season of approximately 202 days.

At an elevation of 1,374 feet, Edwards County receives approximately 35.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Sweet Pea during the growing season.

Annual Blooms in Spring Pollinator-friendly Good for cutting Fragrant
Edwards County, IL (Zone 6b) Long season
202 days
Last Spring Frost April 9
202 growing days
First Fall Frost October 28

Edwards County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.2

Drainage

Well Drained

Sweet Pea Planting Risk Windows

Early Start (70% safe) ✓ Fits season (55 days to spare)
Start indoors: Feb 19 Transplant: Apr 2 🌸 Bloom: Jun 18 – Aug 27
Recommended (50%) ✓ Fits season (55 days to spare)
Start indoors: Feb 26 Transplant: Apr 9 🌸 Bloom: Jun 25 – Sep 3
Safe Start (90%) ✓ Fits season (61 days to spare)
Start indoors: Mar 11 Transplant: Apr 22 🌸 Bloom: Jul 8 – Sep 16

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 Edwards County

How your county's soil matches Sweet Pea's growing requirements.

Soil pH

Your soil pH (6.0–7.2) is more acidic than Sweet Pea prefers (7.0–7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) — Sweet Pea will thrive.

How to Plant Sweet Pea

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Succession Planting Sweet Pea

3
successive plantings in your 202-day season

Sow every 7.4 weeks. Last sowing by Aug 04 to harvest before frost.

Sweet Pea Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 475 gal / 100 sq ft

Monthly Watering Guide for Sweet Pea

Sweet Pea needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Sweet Pea Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 5" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 3.1" 1.2" 💧 Light watering
Oct 4.3" 2.9" 1.4" 💧 Light watering
Nov 2.3" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Edwards County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sweet Pea 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.

Sweet Pea needs ~1,031 GDD — county provides 2,777 GDD Excellent fit

Sweet Pea Planting Timeline — Edwards County, IL

Sweet Pea Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors April 9 Apr 9 – Apr 23
Direct Sow March 5 Mar 5 – Mar 26
Bloom June 25 Jun 25 – Sep 3

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Direct Sow
April Transplant Outdoors
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

65–85 days

🧪 Soil pH

Needs 7–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 6b

📆 Growing Season

202 days in Edwards County

Growing Tips for Sweet Pea in Edwards County

Direct sow Sweet Pea outdoors after April 09 in Edwards County when soil has warmed and frost danger has passed.

Common pests for Sweet Pea in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Soak seeds 24 hours before sowing to soften the hard seed coat; nick the seed coat with a file for the fastest germination. In cold zones (2–6), direct-sow as soon as soil can be worked, 4–6 weeks before last frost; seedlings tolerate light frost but not a hard freeze. In zones 7–9, fall-sow 8–10 weeks before first frost for earlier, stronger spring bloom. Provide a trellis or netting from the start. Feed with low-nitrogen, high-potassium fertilizer once buds form. Pick blooms regularly — even one mature seed pod stops flower production. All plant parts are mildly toxic if eaten.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Pea in Edwards County, IL?

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

What planting zone is Edwards County, IL?

Edwards County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 9 and first fall frost is October 28.

When should I plant Sweet Pea in Edwards County, IL?

In Edwards County, IL, plant Sweet Pea after the last frost (around April 9) and before the first frost (around October 28). Best results when soil holds above 50°F.

What growing zone is Edwards County, IL for Sweet Pea?

Edwards County sits in USDA Zone 6b. Sweet Pea grows reliably in zones 2a through 9b, so it's a good fit here.

Can Sweet Pea grow in Edwards County's climate?

Yes — Sweet Pea grows well in Edwards County's temperate climate. Edwards County averages a 202-day frost-free season, with last frost around April 9 and first frost around October 28.

🌱

Your Edwards County Garden Planner — Free

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.