FrostCal

When to Plant Spinach in Idaho

In a typical Idaho location, sow outdoors Mar 19 – Apr 2. Across the state, the outdoor planting window starts as early as Feb 23 in Lewiston and as late as Apr 5 in Eagle. For a fall crop, plant around Aug 19 – Sep 2. 2 cities in Idaho are essentially frost-free and can plant on a year-round schedule.

Method Direct sow
Days to maturity 40–50 days

Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.

Spinach Planting Dates by City

CityDirect sowFall planting
BoiseMar 13 – Mar 27Aug 26 – Sep 9
MeridianMar 13 – Mar 27Aug 26 – Sep 9
NampaMar 18 – Apr 1Aug 18 – Sep 1
Idaho FallsMar 28 – Apr 11Aug 6 – Aug 20
PocatelloMar 21 – Apr 4Aug 16 – Aug 30
CaldwellMar 12 – Mar 26Aug 23 – Sep 6
Coeur d'AleneMar 11 – Mar 25Aug 23 – Sep 6
Twin FallsMar 19 – Apr 2Aug 14 – Aug 28
LewistonFeb 23 – Mar 9Aug 31 – Sep 14
Lewiston OrchardsFeb 23 – Mar 9Aug 31 – Sep 14
Post FallsMar 11 – Mar 25Aug 23 – Sep 6
RexburgApr 3 – Apr 17Jul 29 – Aug 12
MoscowFrost-free: year-round planting
EagleApr 5 – Apr 19Aug 17 – Aug 31
CondaFrost-free: year-round planting
KunaMar 13 – Mar 27Aug 26 – Sep 9
AmmonMar 28 – Apr 11Aug 6 – Aug 20
ChubbuckMar 21 – Apr 4Aug 16 – Aug 30
HaydenMar 11 – Mar 25Aug 23 – Sep 6
Mountain HomeMar 21 – Apr 4Aug 13 – Aug 27
BlackfootMar 24 – Apr 7Aug 8 – Aug 22
Garden CityMar 13 – Mar 27Aug 26 – Sep 9
JeromeMar 21 – Apr 4Aug 19 – Sep 2
BurleyMar 26 – Apr 9Aug 9 – Aug 23

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 spinach in Idaho?

In a typical Idaho location, sow outdoors Mar 19 – Apr 2. Across the state, the outdoor planting window starts as early as Feb 23 in Lewiston and as late as Apr 5 in Eagle. For a fall crop, plant around Aug 19 – Sep 2. 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 spinach take to grow?

Spinach typically take 40–50 days from planting to harvest. Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.

Other Crops in Idaho

When to plant spinach in other states

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