When to Plant Sweet Pea in Alaska

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.

Alaska spans USDA hardiness zones 2a, 2b, 3b, 4a, 4b, 5a, 5b, 6b, 7a, 7b, 8a (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.

Hover over a county to see details. Click to view planting guide.

Sweet Pea Planting Calendar for Alaska

▸ Zone 2a ~94 day growing season · Full guide →

Last frost: May 30 · First frost: September 1 · 94 day season

Activity	When	Date Range
Start Indoors	April 4	Apr 4 – Apr 18
Transplant Outdoors	May 30	May 30 – Jun 13
Direct Sow	May 2	May 2 – May 23
Bloom	August 22	Aug 22 – Sep 19

▸ Zone 2b ~111 day growing season · Full guide →

Last frost: May 22 · First frost: September 10 · 111 day season

Activity	When	Date Range
Start Indoors	March 27	Mar 27 – Apr 10
Transplant Outdoors	May 22	May 22 – Jun 5
Direct Sow	April 24	Apr 24 – May 15
Bloom	August 14	Aug 14 – Sep 18

▸ Zone 3b ~135 day growing season · Full guide →

Last frost: May 10 · First frost: September 22 · 135 day season

Activity	When	Date Range
Start Indoors	March 22	Mar 22 – Apr 5
Transplant Outdoors	May 10	May 10 – May 24
Direct Sow	April 12	Apr 12 – May 3
Bloom	August 2	Aug 2 – Sep 13

▸ Zone 4a ~145 day growing season · Full guide →

Last frost: May 6 · First frost: September 28 · 145 day season

Activity	When	Date Range
Start Indoors	March 18	Mar 18 – Apr 1
Transplant Outdoors	May 6	May 6 – May 20
Direct Sow	April 1	Apr 1 – Apr 22
Bloom	July 29	Jul 29 – Sep 9

▸ Zone 4b ~155 day growing season · Full guide →

Last frost: May 1 · First frost: October 3 · 155 day season

Activity	When	Date Range
Start Indoors	March 20	Mar 20 – Apr 3
Transplant Outdoors	May 1	May 1 – May 15
Direct Sow	March 27	Mar 27 – Apr 17
Bloom	July 24	Jul 24 – Sep 11

▸ Zone 5a ~166 day growing season · Full guide →

Last frost: April 25 · First frost: October 8 · 166 day season

Activity	When	Date Range
Start Indoors	March 14	Mar 14 – Mar 28
Transplant Outdoors	April 25	Apr 25 – May 9
Direct Sow	March 21	Mar 21 – Apr 11
Bloom	July 11	Jul 11 – Sep 12

▸ Zone 5b ~178 day growing season · Full guide →

Last frost: April 18 · First frost: October 13 · 178 day season

Activity	When	Date Range
Start Indoors	March 7	Mar 7 – Mar 21
Transplant Outdoors	April 18	Apr 18 – May 2
Direct Sow	March 14	Mar 14 – Apr 4
Bloom	July 4	Jul 4 – Sep 5

▸ 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

▸ Zone 7b ~235 day growing season · Full guide →

Last frost: March 18 · First frost: November 8 · 235 day season

Activity	When	Date Range
Bloom	November 22	Nov 22 – Feb 14
Fall Sowing	September 13	Sep 13 – Sep 27

▸ Zone 8a ~255 day growing season · Full guide →

Last frost: March 8 · First frost: November 18 · 255 day season

Activity	When	Date Range
Bloom	November 25	Nov 25 – Feb 17
Fall Sowing	September 16	Sep 16 – Sep 30

Growing Tips for Alaska

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.

Sweet Pea in Other States

Frequently Asked Questions

When should I plant Sweet Pea in Alaska?

Planting dates for Sweet Pea in Alaska depend on your USDA zone. Alaska spans zones 2a, 2b, 3b, 4a, 4b, 5a, 5b, 6b, 7a, 7b, 8a. Check the planting calendar above for your specific zone's frost dates and planting windows.

What zone is Alaska for planting?

Alaska contains USDA hardiness zones 2a, 2b, 3b, 4a, 4b, 5a, 5b, 6b, 7a, 7b, 8a. 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.

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