When to plant Sweet Pea in Clay County County,
In Clay County County, Sweet Pea is a single-season spring crop — there's no second fall window. Plant April 6–April 27 for an 85-day harvest, finishing well before the September 30 first frost.
When to Plant Sweet Pea in Clay County, MN
Top priorities for Clay County, Minnesota gardeners in June
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
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Indoor seed-starting week for sweet pea
Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.
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.
Clay County, Minnesota is in USDA Zone 4a. The average last spring frost is May 11 and the first fall frost is September 30, giving you a growing season of approximately 142 days.
At an elevation of 1,220 feet, Clay County receives approximately 35.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Sweet Pea to ensure they mature before fall.
Clay County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.9
Drainage
Well Drained
Sweet Pea 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 Clay County
How your county's soil matches Sweet Pea's growing requirements.
Soil pH
Your soil pH (5.9–6.9) is more acidic than Sweet Pea prefers (7.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Clay County is excellent for Sweet Pea — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.6%) — Sweet Pea will thrive.
How to Plant Sweet Pea
Succession Planting Sweet Pea
Sow every 7.4 weeks. Last sowing by Jul 07 to harvest before frost.
Sweet Pea Water Budget
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.8" | 0" | ❄️ Dormant |
| Apr | — | 3.9" | 0" | ❄️ Dormant |
| May | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Jun | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Jul | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Sep | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Oct | — | 2.6" | 0" | ❄️ Dormant |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Clay 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 Planting Timeline — Clay County, MN
Sweet Pea Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 23 | Mar 23 – Apr 6 |
| Transplant Outdoors | May 11 | May 11 – May 25 |
| Direct Sow | April 6 | Apr 6 – Apr 27 |
| Bloom | August 3 | Aug 3 – Sep 14 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
65–85 days
🧪 Soil pH
Needs 7–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 4a
📆 Growing Season
142 days in Clay County
Growing Tips for Sweet Pea in Clay County
Direct sow Sweet Pea outdoors after May 11 in Clay 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 →
Sweet Pea in Other Locations
Frequently Asked Questions
When should I plant Sweet Pea in Clay County, MN?
Clay County is in Zone 4a with an average last frost of May 11. Plan your Sweet Pea planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clay County, MN?
Clay County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 11 and first fall frost is September 30.
When should I plant Sweet Pea in Clay County County, ?
In Clay County County, , plant Sweet Pea after the last frost (around May 11) and before the first frost (around September 30). Best results when soil holds above 50°F.
What growing zone is Clay County County, for Sweet Pea?
Clay County County sits in USDA Zone 4a. Sweet Pea grows reliably in zones 2a through 9b, so it's a good fit here.
Can Sweet Pea grow in Clay County County's climate?
Yes — Sweet Pea grows well in Clay County County's temperate climate. Clay County County averages a 142-day frost-free season, with last frost around May 11 and first frost around September 30.
Your Clay County Garden Planner — Free
A 22-page printable planner built for Clay County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.