🥔 Potato

Solanum tuberosum
Underground treasure that occasionally tries to poison you.
Sun
Full sun, 6–8 hrs
Days to harvest
60–100 days depending on type
Spacing
12 inches apart, rows 30–36 inches apart
Soil pH
5.0–6.5 (acidic soil suppresses scab)

How to grow

Plant certified disease-free SEED potatoes (not grocery store — those carry disease and sprout inhibitors), cut into 1.5–2 oz pieces with 2–3 eyes each, and let the cuts cure 2–3 days. Plant 3–4 inches deep, eyes up, 2–4 weeks before last frost — potatoes tolerate light frost and the soil is cool.

HILL — this is the whole game. As vines grow, mound soil (or straw, or compost) around stems so developing tubers stay buried; light turns them green with solanine, which is toxic. Hill twice: once at 6 inches tall, again at 12. In Florida, plant January–February for spring harvest (summer heat rots them); try grow bags or towers where soil stays cooler. In the North, main-crop types store all winter.

Water & feeding

Even moisture — about 1–1.5 inches per week, critical during tuber formation (flowering stage). Stop watering when vines die back; wet soil at harvest = rot in storage. Work worm castings into the planting trench (5–10% by volume); potatoes are moderate feeders but hate fresh manure (causes scab).

Common problems

  • Colorado potato beetles: hand-pick daily (check leaf undersides for orange egg masses), or spinosad. Relentless but beatable.
  • Late blight (Phytophthora infestans — the Irish Potato Famine pathogen): destroy infected foliage immediately, don't compost it, water at soil level. Resistant varieties are the real answer.
  • Scab: rough corky patches — cosmetic, from alkaline soil or fresh manure. Keep pH below 6.0 and use finished compost only.

Harvest

New potatoes: steal a few 2–3 weeks after flowering. Main harvest: wait until vines die back completely, then wait 2 more weeks for skins to set. Dig with a fork, starting from outside. Cure 1–2 weeks in dark, humid, 50–60°F conditions; store in total darkness — light makes solanine, and green potatoes are not a fun surprise.

Nerdy fact: Potatoes were domesticated in the Andes 7,000+ years ago, where thousands of varieties still grow — purple, knobby, finger-shaped. The global potato industry runs on a tiny genetic slice of that diversity, which is exactly the kind of bottleneck that caused the famine. Diversity isn't just pretty; it's insurance.

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