Blog

When to Plant Sweet Pea in Kansas

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.

Kansas spans USDA hardiness zones 6a, 6b, 7a (with planting data available), so planting dates vary by your location within the state. Click your zone below for the most accurate dates.

Find Your County

Click your county for exact Sweet Pea planting dates based on your local frost dates.

Sweet Pea Planting Calendar for Kansas

Zone 6a ~193 day growing season · Full guide →

Last frost: April 10 · First frost: October 20 · 193 day season

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors April 10 Apr 10 – Apr 24
Direct Sow March 6 Mar 6 – Mar 27
Bloom June 26 Jun 26 – Sep 4
Zone 6b ~205 day growing season · Full guide →

Last frost: April 3 · First frost: October 25 · 205 day season

Activity When Date Range
Start Indoors February 20 Feb 20 – Mar 6
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow February 27 Feb 27 – Mar 20
Bloom June 19 Jun 19 – Aug 28
Zone 7a ~221 day growing season · Full guide →

Last frost: March 25 · First frost: November 1 · 221 day season

Activity When Date Range
Direct Sow February 18 Feb 18 – Mar 11
Bloom April 29 Apr 29 – Jul 22
Fall Sowing September 6 Sep 6 – Sep 20

Growing Tips for Kansas

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.

Frequently Asked Questions

When should I plant Sweet Pea in Kansas?

Planting dates for Sweet Pea in Kansas depend on your USDA zone. Kansas spans zones 6a, 6b, 7a. Check the planting calendar above for your specific zone's frost dates and planting windows.

What zone is Kansas for planting?

Kansas contains USDA hardiness zones 6a, 6b, 7a. Your specific zone depends on your location within the state — northern and higher-elevation areas are in colder zones, while southern and coastal areas are warmer.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Last updated: June 2026.