Washington DC · zones 7b–7b
When to plant potatoes in Washington DC.
Sow between Feb 26 to Mar 31 in a typical year, keyed to Washington DC's median last frost around Apr 5. A second, fall sowing fits Jul 21 to Aug 3. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Potatoes dates for a typical Washington DC season.
Direct sow
Feb 26 to Mar 31
Keyed to the ~Apr 5 last frost. Sow 4" deep, 12" apart.
Fall round
Jul 21 to Aug 3
Counted back from the ~Nov 8 first frost.
Harvest
~90 days later
~3 lb per plant over ~1 weeks.
Washington DC spans more than one climate: Zone 7 is the most common zone, but the state runs 7b to 7b. 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 Washington DC: watch for
The pests that find potatoes here.
A middle-length season, about 217 frost-free days, means potato overlaps colorado potato beetle for a stretch each summer. Check plants every week or two and treat early.
Striped beetles and orange grubs eating the leaves.
Organic fix: Handpick adults, crush the orange egg clusters, dust with diatomaceous earth.
Dark greasy blotches after cool, wet spells.
Organic fix: Pull infected plants fast, keep leaves dry, use neem as a preventive.
Common scab
Rough, corky patches on the skin, raised on some tubers and sunk into pits on others.
Organic fix: Keep the bed evenly moist through the weeks right after tubers set, rotate away from potatoes, and pick a scab-resistant variety next time.
Your season math: Washington DC gives potatoes about 217 frost-free days, and it needs roughly 90 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting potatoes in Washington DC: questions
When should I plant potatoes in Washington DC?+
In a typical Washington DC year, sow potatoes between Feb 26 to Mar 31, keyed to the state's median last frost around Apr 5. There's also a fall window: Jul 21 to Aug 3. Your exact dates shift with your ZIP code and microclimate.
What USDA zone is Washington DC?+
Washington DC spans zones 7b–7b, mostly zone 7. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many 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.