What you need to know.
Potatoes follow a rule in NC: plant them on St. Patrick's Day, March 17th. That is the traditional date for Zone 7b and it works. Soil temperatures are just coming up, there is still time before summer heat arrives, and the timing gives plants enough of a cool growing season to set a good crop before things get too warm. My dad told me the St. Patrick's Day rule my first year and I have stuck to it.
I grow three varieties: Kennebec (a classic russet type, stores well), Yukon Gold (buttery yellow flesh, my favorite for roasting), and Red Pontiac (red-skinned, waxy texture, great for smashing and crisping). Each one behaves a little differently but all three grow reliably in Zone 7b. Yukon Gold is the one I would plant if I could only choose one.
"My first potato harvest felt like a treasure hunt. You dig the fork in and potatoes come flying out of the soil. I did not expect to find so many."
Step by step.
Buy certified seed potatoes, not grocery store ones — grocery potatoes are often treated to prevent sprouting. Cut seed potatoes into egg-sized chunks, each with at least 2 eyes (the small dimples where sprouts emerge). Lay the cut pieces out in a single layer for 2 days before planting so the cut surface dries and forms a callus, which reduces rot.
Plant cut-side down, 4 inches deep, 12 inches apart in rows 3 feet apart. As the plants grow, mound soil up around the base when they reach about 8 inches tall. Repeat this hilling process every couple of weeks — exposed tubers turn green and bitter. Keep them buried.
About 2 to 3 weeks after the plant flowers, you can dig carefully around the edge of the plant for small new potatoes. For a full harvest, wait until the foliage yellows and dies back completely, then dig the whole plant.
When to plant in Zone 7b.
In Zone 7b, plant around March 17th. Potato plants can handle light frost — if a late frost threatens, just hill more soil over them or cover with a cloth. They are tougher than they look in early spring.
Harvest in late June or July when the tops die back. After digging, let potatoes cure in a dark, dry, well-ventilated spot at room temperature for about 2 weeks before storing. This toughens the skin and helps them keep for months. Uncured potatoes go soft much faster.
Problems I ran into.
Colorado potato beetles — orange-and-black-striped beetles and their dark red larvae — are my biggest problem. They eat potato leaves aggressively. I check plants every few days and pick off any beetles and egg clusters (bright orange eggs on leaf undersides) by hand. Catching them early makes a big difference.
Blight (late blight specifically) can devastate potatoes in wet summers — dark spots on leaves spread fast and can kill plants before harvest. I plant disease-resistant varieties like Kennebec, which has good blight tolerance, and avoid overhead watering. If blight strikes, harvest immediately and do not compost infected foliage.
What I make with it.
I grow potatoes because of one recipe: smashed and crisped in the oven with olive oil and salt. Boil small potatoes until just tender, smash them flat, roast at 450 degrees until shatteringly crispy. They are one of the best things I have ever cooked.
The full smashed crispy potato recipe is on the recipes page. It works with any variety but Yukon Gold or Red Pontiac give the best results.