FrostCal

When to Plant Basil in Illinois

In a typical Illinois location, start seeds indoors Mar 9 – Mar 16, then transplant outdoors Apr 27 – May 4. Across the state, the outdoor planting window starts as early as Apr 8 in Granite City and as late as May 8 in Roscoe.

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
ChicagoFeb 27 – Mar 6Apr 17 – Apr 24
AuroraMar 8 – Mar 15Apr 26 – May 3
RockfordMar 13 – Mar 20May 1 – May 8
JolietMar 8 – Mar 15Apr 26 – May 3
NapervilleMar 17 – Mar 24May 5 – May 12
PeoriaMar 5 – Mar 12Apr 23 – Apr 30
SpringfieldMar 4 – Mar 11Apr 22 – Apr 29
North PeoriaMar 5 – Mar 12Apr 23 – Apr 30
ElginMar 15 – Mar 22May 3 – May 10
WaukeganMar 19 – Mar 26May 7 – May 14
ChampaignMar 4 – Mar 11Apr 22 – Apr 29
CiceroFeb 28 – Mar 7Apr 18 – Apr 25
BloomingtonMar 10 – Mar 17Apr 28 – May 5
Arlington HeightsMar 8 – Mar 15Apr 26 – May 3
EvanstonMar 15 – Mar 22May 3 – May 10
SchaumburgMar 19 – Mar 26May 7 – May 14
BolingbrookMar 9 – Mar 16Apr 27 – May 4
DecaturMar 3 – Mar 10Apr 21 – Apr 28
PalatineMar 14 – Mar 21May 2 – May 9
SkokieMar 15 – Mar 22May 3 – May 10
Des PlainesMar 5 – Mar 12Apr 23 – Apr 30
Orland ParkMar 8 – Mar 15Apr 26 – May 3
Tinley ParkMar 12 – Mar 19Apr 30 – May 7
Oak LawnFeb 27 – Mar 6Apr 17 – Apr 24
BerwynFeb 28 – Mar 7Apr 18 – Apr 25
Mount ProspectMar 8 – Mar 15Apr 26 – May 3
NormalMar 14 – Mar 21May 2 – May 9
WheatonMar 17 – Mar 24May 5 – May 12
Oak ParkFeb 28 – Mar 7Apr 18 – Apr 25
Hoffman EstatesMar 19 – Mar 26May 7 – May 14

Showing the 30 most populous of 242 Illinois cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Illinois cities.

Frequently Asked Questions

When should I plant basil in Illinois?

In a typical Illinois location, start seeds indoors Mar 9 – Mar 16, then transplant outdoors Apr 27 – May 4. Across the state, the outdoor planting window starts as early as Apr 8 in Granite City and as late as May 8 in Roscoe.

When is the last frost in Illinois?

The average last spring frost in Illinois ranges from April 1 in Granite City to May 1 in Roscoe, 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 Illinois

When to plant basil in other states

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