When to Plant Lettuce in Colorado
Colorado spans USDA hardiness 4a to 7a (zones 4a to 7a on this page). Plant lettuce by your local frost date, not the calendar — pick your zone below for exact start-indoors, transplant, and harvest dates.
Jump to: Zone 4a · Zone 4b · Zone 5a · Zone 5b · Zone 6a · Zone 6b · Zone 7a
Lettuce planting calendar for Colorado, Zone 4a
Average last spring frost
May 15
Average first fall frost
September 20
spring planting
Start seeds indoors
Mar 27
Transplant outdoors
May 1
Projected first harvest
Jun 25
fall planting
Direct sow
Jul 12
Projected first harvest
Sep 5
spring planting
fall planting
Most lettuce mature in about 45 to 85 days depending on the variety. Full zone 4 guide (both 4a and 4b) →
Lettuce planting calendar for Colorado, Zone 4b
Average last spring frost
May 10
Average first fall frost
September 25
spring planting
Start seeds indoors
Mar 22
Transplant outdoors
Apr 26
Projected first harvest
Jun 20
fall planting
Direct sow
Jul 17
Projected first harvest
Sep 10
spring planting
fall planting
Most lettuce mature in about 45 to 85 days depending on the variety. Full zone 4 guide (both 4a and 4b) →
Lettuce planting calendar for Colorado, Zone 5a
Average last spring frost
May 5
Average first fall frost
October 1
spring planting
Start seeds indoors
Mar 17
Transplant outdoors
Apr 21
Projected first harvest
Jun 15
fall planting
Direct sow
Jul 23
Projected first harvest
Sep 16
spring planting
fall planting
Most lettuce mature in about 45 to 85 days depending on the variety. Full zone 5 guide (both 5a and 5b) →
Lettuce planting calendar for Colorado, Zone 5b
Average last spring frost
April 30
Average first fall frost
October 5
spring planting
Start seeds indoors
Mar 12
Transplant outdoors
Apr 16
Projected first harvest
Jun 10
fall planting
Direct sow
Jul 27
Projected first harvest
Sep 20
spring planting
fall planting
Most lettuce mature in about 45 to 85 days depending on the variety. Full zone 5 guide (both 5a and 5b) →
Lettuce planting calendar for Colorado, Zone 6a
Average last spring frost
April 25
Average first fall frost
October 10
spring planting
Start seeds indoors
Mar 7
Transplant outdoors
Apr 11
Projected first harvest
Jun 5
fall planting
Direct sow
Aug 1
Projected first harvest
Sep 25
spring planting
fall planting
Most lettuce mature in about 45 to 85 days depending on the variety. Full zone 6 guide (both 6a and 6b) →
Lettuce planting calendar for Colorado, Zone 6b
Average last spring frost
April 20
Average first fall frost
October 15
spring planting
Start seeds indoors
Mar 2
Transplant outdoors
Apr 6
Projected first harvest
May 31
fall planting
Direct sow
Aug 6
Projected first harvest
Sep 30
spring planting
fall planting
Most lettuce mature in about 45 to 85 days depending on the variety. Full zone 6 guide (both 6a and 6b) →
Lettuce planting calendar for Colorado, Zone 7a
Average last spring frost
April 15
Average first fall frost
October 20
spring planting
Start seeds indoors
Feb 25
Transplant outdoors
Apr 1
Projected first harvest
May 26
fall planting
Direct sow
Aug 11
Projected first harvest
Oct 5
spring planting
fall planting
Most lettuce mature in about 45 to 85 days depending on the variety. Full zone 7 guide (both 7a and 7b) →
Not sure which half-zone you're in? Set your ZIP in HomeSown for dates tuned to your exact location.
Varieties to grow
12 varieties of lettuce in the HomeSown library. Tap any for its full grow guide.
Common problems with lettuce
What to watch for, with identification and treatment for each
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