When to plant sweet potato in Duluth
Sweet potato is frost-tender, so every date keys off Duluth's last spring frost of May 10.
Step 1 · Plant
Transplant outdoors
Jul 14 – Aug 4
Once frost risk has passed and nights stay mild.
Step 2 · Harvest
Harvest window
Oct 12 – Nov 11
Picking runs until conditions turn against the crop.
Window
Days to maturity
90 – 120 d
Duluth's 150-day season leaves this much room.
Sweet potato on Duluth's growing year
Frost-bounded season with crops mapped onto the 12-month axis.
Frost risk Growing Harvest
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
FROST
FROST
MAY 10
OCT 7
Common questions
When will sweet potato be ready to harvest in Duluth?
Expect to harvest from around mid October (Oct 12–Nov 11) in Duluth, based on its local frost dates. Confidence 78%.
When can I transplant sweet potato outdoors in Duluth?
Transplant outdoors around mid July (Jul 14–Aug 4) in Duluth, based on its local frost dates. Confidence 84%.
How long is the growing season in Duluth?
Duluth has roughly 150 frost-free days, which is enough time to grow sweet potato to maturity outdoors.
The rule of thumb
Sow sweet potato 6–8 weeks before your last spring frost; plant out 2–3 weeks after it. Every date on this page is derived from that rule and Duluth's frost dates.
Confidence 87/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.