🌽 Corn

Zea mays
The only vegetable that is also a grass having an identity crisis.
Sun
Full sun, 8+ hrs — corn is a solar panel with commitment issues about shade
Days to harvest
60–100 days depending on variety
Spacing
Plant in blocks (not single rows) for pollination; 12 inches apart, rows 30–36 inches apart
Soil pH
5.8–7.0

How to grow

Direct sow only — corn despises transplanting the way cats despise closed doors. Wait until soil is a genuine 60°F+ (stick a thermometer in; guessing is how you get seeds that sit there judging you). Plant seeds 1–2 inches deep. The critical thing: plant in a BLOCK, minimum 4×4, because corn is wind-pollinated and each silk must meet a pollen grain. A single row of corn is just a very tall, very lonely decoration.

In Florida, you get two shots: spring (after last frost) and a late-summer planting for fall harvest. Up north, pick varieties under 75 days to maturity or you're racing the first frost. Hill soil slightly around stalks when they're knee-high — corn grows brace roots that look like tiny stilts, and hilling gives them something to grab.

Water & feeding

Corn is thirsty — about 1–1.5 inches per week, and non-negotiable during tasseling and silk emergence, when drought turns kernels into sad little blanks. It's also a nitrogen hog; work worm castings (5–10% by volume) into the planting bed and side-dress with more castings or compost when plants are knee-high and again at tasseling.

Common problems

  • Earworms (Helicoverpa zea): dab a drop of mineral oil on silks after pollination, or release Trichogramma wasps — tiny parasitoids that are the special forces of the insect world.
  • Smudged, half-filled ears: poor pollination. Plant bigger blocks next time, or hand-pollinate by shaking tassels over silks like you're seasoning them.
  • Corn smut (Ustilago maydis): those gray galls are actually a delicacy (huitlacoche) in Mexico. If you're not into that, remove and destroy galls before they burst.

Harvest

Harvest when silks are brown and dry and the ear feels full; puncture a kernel — milky juice means go, watery means wait, doughy means you waited too long. Twist and pull downward. Eat within hours if possible; sugars convert to starch fast, which is why store corn tastes like sweetened cardboard.

Nerdy fact: Each silk connects to exactly one kernel — so a half-filled ear is just a census of which silks never got pollinated. Corn is essentially doing mail delivery with the wind.

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