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When to Plant Nasturtium in Alaska

Nasturtium (Tropaeolum majus) is a fast-growing annual with distinctive round, lily-pad leaves and bold trumpet-shaped blooms in warm oranges, reds, and yellows. Both the flowers and leaves are edible with a peppery watercress flavor. Planted near vegetables, nasturtiums act as a sacrifice trap-crop, luring aphids away from more valuable plants. They thrive in poor, dry soil — rich conditions produce lush foliage but few flowers.

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 Nasturtium planting dates based on your local frost dates.

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

Nasturtium 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 May 2 May 2 – May 16
Transplant Outdoors June 13 Jun 13 – Jun 27
Direct Sow June 13 Jun 13 – Jul 4
Bloom August 8 Aug 8 – Oct 3
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 April 24 Apr 24 – May 8
Transplant Outdoors June 5 Jun 5 – Jun 19
Direct Sow June 5 Jun 5 – Jun 26
Bloom July 31 Jul 31 – Oct 2
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 April 12 Apr 12 – Apr 26
Transplant Outdoors May 24 May 24 – Jun 7
Direct Sow May 24 May 24 – Jun 14
Bloom July 19 Jul 19 – Sep 27
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 April 8 Apr 8 – Apr 22
Transplant Outdoors May 20 May 20 – Jun 3
Direct Sow May 20 May 20 – Jun 10
Bloom July 15 Jul 15 – Sep 30
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 April 3 Apr 3 – Apr 17
Transplant Outdoors May 8 May 8 – May 22
Direct Sow May 8 May 8 – May 29
Bloom July 3 Jul 3 – Sep 25
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 28 Mar 28 – Apr 11
Transplant Outdoors May 2 May 2 – May 16
Direct Sow May 2 May 2 – May 23
Bloom June 27 Jun 27 – Oct 3
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 21 Mar 21 – Apr 4
Transplant Outdoors April 25 Apr 25 – May 9
Direct Sow April 25 Apr 25 – May 16
Bloom June 20 Jun 20 – Oct 3
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 March 6 Mar 6 – Mar 20
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow April 3 Apr 3 – Apr 24
Bloom May 29 May 29 – Sep 25
Zone 7a ~221 day growing season · Full guide →

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

Activity When Date Range
Start Indoors February 25 Feb 25 – Mar 11
Transplant Outdoors March 25 Mar 25 – Apr 8
Direct Sow March 25 Mar 25 – Apr 15
Bloom May 20 May 20 – Sep 23
Zone 7b ~235 day growing season · Full guide →

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

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors March 18 Mar 18 – Apr 1
Direct Sow March 18 Mar 18 – Apr 8
Bloom May 13 May 13 – Sep 30
Zone 8a ~255 day growing season · Full guide →

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

Activity When Date Range
Start Indoors February 8 Feb 8 – Feb 22
Transplant Outdoors March 1 Mar 1 – Mar 15
Direct Sow March 1 Mar 1 – Mar 22
Bloom April 26 Apr 26 – Sep 27

Growing Tips for Alaska

Direct-sow large seeds 1/2 inch deep after last frost; soak seeds overnight to speed germination (7-10 days). Nasturtiums dislike root disturbance so direct sowing is strongly preferred. Avoid fertilizing — poor soil brings the best bloom. Trailing types can cover banks and climb trellises; dwarf types suit containers. In hot climates (zones 9+) plant in fall for winter/spring bloom as plants struggle in peak summer heat.

Frequently Asked Questions

When should I plant Nasturtium in Alaska?

Planting dates for Nasturtium 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.

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