When should I plant Sweet Potato in Zone 3b?

Start Sweet Potato seeds indoors around Mar 20. Transplant outdoors after Jun 5. Expect first harvest around Sep 3.

What is the last frost date for Zone 3b?

The average last spring frost date for Zone 3b is May 15. The first fall frost averages Sep 22, giving a 130-day growing season.

Can I grow Sweet Potato in Zone 3b?

Yes. Sweet Potato needs 100 days to harvest. Zone 3b has a 130-day growing season, which is sufficient.

🍠

🍠 Growing Sweet Potato in Zone 3b

Zone 3b has harsh winters and a short growing season. Start Sweet Potato early indoors to maximize your harvest window. Last frost: May 15. First frost: Sep 22.

Planting Calendar

Indoor

Outdoor

Harvest

Mar 20Sep 22

Season: May 15 – Sep 22 (130 days)

Zone3b

Last FrostMay 15

First FrostSep 22

Season Length130 days

Days to Harvest100

SunFull Sun

Frost ToleranceNone

Spacing1/sqft (12" apart)

When to Plant Sweet Potato in Zone 3b

Start Seeds Indoors: Mar 20

Start Sweet Potato seeds indoors around Mar 20 (8 weeks before last frost). Optimal germination temperature: 85°F. Germinates in 14–21 days.

Transplant Outdoors: Jun 5

Transplant Sweet Potato seedlings outdoors after Jun 5. Wait until soil temperature reaches 65°F. Space plants at 1/sqft (12" apart). Harden off plants for a week before moving outside.

Harvest: Sep 3

First harvest approximately Sep 3 (~90 days from transplant). Continue harvesting until first frost (Sep 22).

Companion Planting

✅ Dill ✅ Oregano ✅ Thyme

Sweet Potato in Other Zones

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Plan Your Sweet Potato Garden

Track Sweet Potato from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

Start Free Sweet Potato Growing Guide