When to Plant Begonias in Alaska

Wax begonias (Begonia × semperflorens) are the workhorse shade bedding plant of American horticulture, offering continuous bloom from transplant to hard frost. Bronze or green-leaved varieties perform well from deep shade to full sun (in northern zones) and tolerate summer humidity better than most cool- season flowers. A staple of mass plantings, containers, and window boxes.

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 Begonias planting dates based on your local frost dates.

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

Begonias 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 7	Mar 7 – Mar 21
Transplant Outdoors	June 13	Jun 13 – Jun 27
Bloom	August 22	Aug 22 – 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	February 27	Feb 27 – Mar 13
Transplant Outdoors	June 5	Jun 5 – Jun 19
Bloom	August 14	Aug 14 – 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	February 22	Feb 22 – Mar 8
Transplant Outdoors	May 24	May 24 – Jun 7
Bloom	August 2	Aug 2 – 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	February 18	Feb 18 – Mar 4
Transplant Outdoors	May 20	May 20 – Jun 3
Bloom	July 29	Jul 29 – 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 13	Feb 13 – Feb 27
Transplant Outdoors	May 8	May 8 – May 22
Bloom	July 17	Jul 17 – 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	February 14	Feb 14 – Feb 28
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 7	Feb 7 – Feb 21
Transplant Outdoors	April 25	Apr 25 – May 9
Bloom	July 4	Jul 4 – Sep 26

▸ 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	January 23	Jan 23 – Feb 6
Transplant Outdoors	April 10	Apr 10 – Apr 24
Bloom	June 19	Jun 19 – 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	January 14	Jan 14 – Jan 28
Transplant Outdoors	March 25	Mar 25 – Apr 8
Bloom	June 3	Jun 3 – 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	January 7	Jan 7 – Jan 21
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	December 28	Dec 28 – Jan 11
Transplant Outdoors	March 1	Mar 1 – Mar 15
Bloom	May 10	May 10 – Sep 27

Growing Tips for Alaska

Start seeds indoors 10–12 weeks before last frost — seed is dust-fine; surface-sow on moist mix under lights, do not cover. Bottom heat (70–75°F) speeds germination. Transplant after frost; begonias are not direct-sown in practice. Pinch seedlings once for branching. Keep soil evenly moist; avoid waterlogged conditions. Bronze-leaf types tolerate more sun; green- leaf types prefer shade to part-sun.

Begonias in Other States

Frequently Asked Questions

When should I plant Begonias in Alaska?

Planting dates for Begonias 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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