Rhode Island · zones 6b–7a
When to plant sweet potatoes in Rhode Island.
Sow or transplant between May 17 to Jun 25 in a typical year, keyed to Rhode Island's median last frost around Apr 10. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Sweet Potatoes dates for a typical Rhode Island season.
1 · Start indoors
Apr 5 to May 14
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
May 17 to Jun 25
Keyed to the ~Apr 10 last frost. Sow 3" deep, 14" apart.
Harvest
~110 days later
~2.5 lb per plant over ~1 weeks.
Rhode Island spans more than one climate: Zone 6 is the most common zone, but the state runs 6b to 7a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
In Rhode Island: watch for
The pests that find sweet potatoes here.
A middle-length season, about 200 frost-free days, means sweet potato overlaps wireworms & white grubs for a stretch each summer. Check plants every week or two and treat early.
Wireworms & white grubs
Shallow holes and grooves chewed into the roots, found only at digging time.
Organic fix: Avoid planting into ground that was in sod last year; rotate away from grassy beds.
Clusters on the tender growing tips of new vines.
Organic fix: Hose them off in the morning, or use insecticidal soap.
Black rot
Dry, firm dark patches on the roots, usually found at harvest or in storage, with a sweet fruity smell.
Organic fix: Start from clean slips cut well above the soil line, never save roots from a bad crop, and rotate 3 years.
Your season math: Rhode Island gives sweet potatoes about 200 frost-free days, and it needs roughly 110 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting sweet potatoes in Rhode Island: questions
When should I plant sweet potatoes in Rhode Island?+
In a typical Rhode Island year, sow sweet potatoes or set out transplants between May 17 to Jun 25, keyed to the state's median last frost around Apr 10. Your exact dates shift with your ZIP code and microclimate.
When do I start sweet potatoes seeds indoors in Rhode Island?+
Start seeds inside about 6 weeks before set-out: roughly Apr 5 to May 14 for a typical Rhode Island season.
What USDA zone is Rhode Island?+
Rhode Island spans zones 6b–7a, mostly zone 6. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many sweet potatoes plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.