When to Plant Impatiens in Alaska

Impatiens (Impatiens walleriana) are the go-to annual for shaded beds and containers. They produce a continuous carpet of flat-faced blooms from transplant until frost, needing little deadheading. Their preference for consistent moisture and part-shade makes them ideal under trees and along north-facing borders.

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.

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

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

Impatiens 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	March 21	Mar 21 – Apr 4
Transplant Outdoors	June 13	Jun 13 – Jun 27
Bloom	September 5	Sep 5 – Sep 26

▸ 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 13	Mar 13 – Mar 27
Transplant Outdoors	June 5	Jun 5 – Jun 19
Bloom	August 21	Aug 21 – Sep 25

▸ 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 8	Mar 8 – Mar 22
Transplant Outdoors	May 24	May 24 – Jun 7
Bloom	August 9	Aug 9 – 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	March 4	Mar 4 – Mar 18
Transplant Outdoors	May 20	May 20 – Jun 3
Bloom	August 5	Aug 5 – 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	February 27	Feb 27 – Mar 13
Transplant Outdoors	May 15	May 15 – May 29
Bloom	July 31	Jul 31 – Oct 2

▸ 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	February 28	Feb 28 – Mar 14
Transplant Outdoors	May 2	May 2 – May 16
Bloom	July 11	Jul 11 – 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	February 21	Feb 21 – Mar 7
Transplant Outdoors	April 25	Apr 25 – May 9
Bloom	July 4	Jul 4 – 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	February 6	Feb 6 – Feb 20
Transplant Outdoors	April 10	Apr 10 – Apr 24
Bloom	June 19	Jun 19 – Oct 2

▸ 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	January 28	Jan 28 – Feb 11
Transplant Outdoors	April 1	Apr 1 – Apr 15
Bloom	June 10	Jun 10 – Sep 30

▸ 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	January 21	Jan 21 – Feb 4
Transplant Outdoors	March 18	Mar 18 – Apr 1
Bloom	May 27	May 27 – 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	January 11	Jan 11 – Jan 25
Transplant Outdoors	March 8	Mar 8 – Mar 22
Bloom	May 17	May 17 – Oct 4

Growing Tips for Alaska

Start seeds indoors 8–10 weeks before last frost at 70–75°F; germination requires light — do not cover seeds. Transplant after last frost once nights consistently exceed 50°F. Water regularly — wilting causes bud drop and they rarely fully recover the same flush. Watch for impatiens downy mildew (IDM); consider New Guinea impatiens as a resistant alternative in affected regions. Pinch tips at planting to encourage branching.

Impatiens in Other States

Frequently Asked Questions

When should I plant Impatiens in Alaska?

Planting dates for Impatiens 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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