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When to plant Sweet Pea in Sumner County County,

Sumner County County sits in USDA Zone 7a. Plant Sweet Pea between March 7 (after last frost on April 11) and March 28. A second sowing from August 31 to September 14 extends the harvest into fall.

When to Plant Sweet Pea in Sumner County, KS

Sumner County, Kansas Zone 7a June

What to do in June

We've pulled the most time-sensitive tasks for Sumner County, Kansas this June and put them front and centre. Tackle them in order.

Avg. last frost April 11
Avg. first frost October 26
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 14.5 hrs
  1. It's harvest week for sweet pea

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

To set up a strong July, finish these tasks
  • First harvests: sweet pea

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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.

Sumner County, Kansas is in USDA Zone 7a. The average last spring frost is April 11 and the first fall frost is October 26, giving you a growing season of approximately 198 days.

At an elevation of 637 feet, Sumner County receives approximately 29 inches of rainfall annually with predominantly 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
Sumner County, KS (Zone 7a) Moderate season
198 days
Last Spring Frost April 11
198 growing days
First Fall Frost October 26

Sumner County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.8

Drainage

Well Drained

Sweet Pea Planting Risk Windows

Early Start (70% safe) ✓ Fits season (45 days to spare)
Transplant: Apr 5 🌸 Bloom: Jun 14 – Sep 6
Recommended (50%) ✓ Fits season (44 days to spare)
Transplant: Apr 11 🌸 Bloom: Jun 20 – Sep 12
Safe Start (90%) ✓ Fits season (47 days to spare)
Transplant: Apr 25 🌸 Bloom: Jul 4 – 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 Sumner County

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

Soil pH

Your soil pH (6.4–7.8) overlaps with Sweet Pea's range (7.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.6%). Annual compost additions will help Sweet Pea.

How to Plant Sweet Pea

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Sweet Pea

3
successive plantings in your 198-day season

Sow every 7.4 weeks. Last sowing by Aug 02 to harvest before frost.

For a dedicated fall crop, sow by Aug 31.

Sweet Pea Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 814 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 0.7" 0" ❄️ Dormant
Feb 1.1" 0" ❄️ Dormant
Mar 1.7" 0" ❄️ Dormant
Apr 4.3" 3" 1.3" 💧 Light watering
May 4.3" 4.4" 0" ✅ Rainfall sufficient
Jun 4.3" 4.2" 0.1" 💧 Light watering
Jul 4.3" 3.4" 0.9" 💧 Light watering
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 3" 1.3" 💧 Light watering
Oct 4.3" 1.7" 2.6" 🚿 Regular watering
Nov 1.1" 0" ❄️ Dormant
Dec 0.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Sumner 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 2,722 GDD Excellent fit

Sweet Pea Planting Timeline — Sumner County, KS

Sweet Pea Planting Calendar

Activity When Date Range
Direct Sow March 7 Mar 7 – Mar 28
Bloom May 16 May 16 – Aug 8
Fall Sowing August 31 Aug 31 – Sep 14

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

Month-by-Month Timeline

MonthActivities
January
February
March Direct Sow
April
May Bloom
June Bloom
July Bloom
August Fall Sowing Bloom
September Fall Sowing
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

65–85 days

🧪 Soil pH

Needs 7–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

198 days in Sumner County

Growing Tips for Sweet Pea in Sumner County

Direct sow Sweet Pea outdoors after April 11 in Sumner 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 Sumner County, KS?

Sumner County is in Zone 7a with an average last frost of April 11. Plan your Sweet Pea planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sumner County, KS?

Sumner County, Kansas is in USDA Hardiness Zone 7a. The average last spring frost is April 11 and first fall frost is October 26.

When should I plant Sweet Pea in Sumner County County, ?

In Sumner County County, , plant Sweet Pea after the last frost (around April 11) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Sumner County County, for Sweet Pea?

Sumner County County sits in USDA Zone 7a. Sweet Pea grows reliably in zones 2a through 9b, so it's a good fit here.

Can Sweet Pea grow in Sumner County County's climate?

Yes — Sweet Pea grows well in Sumner County County's temperate climate. Sumner County County averages a 198-day frost-free season, with last frost around April 11 and first frost around October 26.

🌱

Your Sumner County Garden Planner — Free

A 22-page printable planner built for Sumner County (Zone 7a). 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 Sumner County, KS. 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.