FrostCal

When to Plant Basil in Idaho

In a typical Idaho location, start seeds indoors Mar 19 – Mar 26, then transplant outdoors May 7 – May 14. Across the state, the outdoor planting window starts as early as Apr 13 in Lewiston and as late as May 24 in Eagle. 2 cities in Idaho are essentially frost-free and can plant on a year-round schedule.

Method Start indoors, then transplant
Days to maturity 50–70 days

Very frost/cold sensitive; start indoors 5-6 weeks before last frost, transplant only after all danger of frost (1-2 weeks after) and nights stay warm.

Basil Planting Dates by City

CityStart indoorsTransplant
BoiseMar 13 – Mar 20May 1 – May 8
MeridianMar 13 – Mar 20May 1 – May 8
NampaMar 18 – Mar 25May 6 – May 13
Idaho FallsMar 28 – Apr 4May 16 – May 23
PocatelloMar 21 – Mar 28May 9 – May 16
CaldwellMar 12 – Mar 19Apr 30 – May 7
Coeur d'AleneMar 11 – Mar 18Apr 29 – May 6
Twin FallsMar 19 – Mar 26May 7 – May 14
LewistonFeb 23 – Mar 2Apr 13 – Apr 20
Lewiston OrchardsFeb 23 – Mar 2Apr 13 – Apr 20
Post FallsMar 11 – Mar 18Apr 29 – May 6
RexburgApr 3 – Apr 10May 22 – May 29
MoscowFrost-free: year-round planting
EagleApr 5 – Apr 12May 24 – May 31
CondaFrost-free: year-round planting
KunaMar 13 – Mar 20May 1 – May 8
AmmonMar 28 – Apr 4May 16 – May 23
ChubbuckMar 21 – Mar 28May 9 – May 16
HaydenMar 11 – Mar 18Apr 29 – May 6
Mountain HomeMar 21 – Mar 28May 9 – May 16
BlackfootMar 24 – Mar 31May 12 – May 19
Garden CityMar 13 – Mar 20May 1 – May 8
JeromeMar 21 – Mar 28May 9 – May 16
BurleyMar 26 – Apr 2May 14 – May 21

Showing the 24 most populous of 24 Idaho cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Idaho cities.

Frequently Asked Questions

When should I plant basil in Idaho?

In a typical Idaho location, start seeds indoors Mar 19 – Mar 26, then transplant outdoors May 7 – May 14. Across the state, the outdoor planting window starts as early as Apr 13 in Lewiston and as late as May 24 in Eagle. 2 cities in Idaho are essentially frost-free and can plant on a year-round schedule.

When is the last frost in Idaho?

The average last spring frost in Idaho ranges from April 6 in Lewiston to May 17 in Eagle, based on NOAA 1991–2020 climate normals.

How long do basil take to grow?

Basil typically take 50–70 days from planting to harvest. Very frost/cold sensitive; start indoors 5-6 weeks before last frost, transplant only after all danger of frost (1-2 weeks after) and nights stay warm.

Other Crops in Idaho

When to plant basil in other states

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