When to plant Lettuce in Maine

In spring, from Mar 20 – May 15 in Auburn to May 1 – June 30 in Sanford.

In fall, from June 1 – Aug 1 in Bangor to July 15 – Sept 1 in Westbrook.

USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.

Leaf lettuce planting dates by place in Maine
PlaceSpringFall
AuburnMar 20 – May 15July 15 – Sept 1
AugustaApr 1 – June 1July 15 – Sept 1
BangorApr 1 – June 1June 1 – Aug 1
BiddefordApr 15 – June 15June 1 – Aug 1
LewistonMar 20 – May 15July 15 – Sept 1
PortlandApr 1 – June 1July 15 – Sept 1
SacoApr 1 – June 1July 15 – Sept 1
SanfordMay 1 – June 30June 1 – Aug 1
South PortlandApr 1 – June 1July 15 – Sept 1
WatervilleApr 1 – June 1July 15 – Sept 1
WestbrookApr 1 – June 1July 15 – Sept 1

Planting dates: USDA Home and Garden Bulletin No. 9 (1967), tables 4 and 5. Frost dates: NOAA U.S. Climate Normals 1991–2020. “—” means the place's frost date is outside the table. The full USDA table for leaf lettuce.