When to Plant : Extremely frost sensitive, corn planted in soils cooler than 55 degrees (65 for super-sweet varieties) fails to germinate or has very poor germination. Direct-sow only after night temperatures are consistently in the 50s. Plant in blocks of at least 3 rows, at least 3 feet long apiece, to ensure best pollination. Hand-pollinate by gently shaking plants toward one another if you cannot devote this much space.
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