Broccoli

Growing Broccoli in Zone 6a

A complete, zone-6a timeline for Broccoli — when to start, transplant, and harvest, tuned to this zone's typical frost dates (St. Louis, Cincinnati, Boston).

April 26Last spring frost
October 12First fall frost
about 169 daysGrowing season
−10 to 0°FWinter low

Your planting timeline

  1. Start seeds indoors~7 weeks before last frost (around March 8)
  2. Harvestabout 60–100 from transplant days from transplant

Best varieties for zone 6a

A wide range thrives; grow dependable Arcadia and Belstar, and add a side-shoot variety like Di Cicco for a long, productive cutting season.

Growing notes

Broccoli needs steady, even moisture — roughly 1 to 1.5 inches per week — to develop large, tender heads. The crop is shallow-rooted and unforgiving of drought: let it dry out at the wrong moment and the head buttons (forms tiny, premature) or turns tough and bitter. Water deeply at the base rather than overhead, which keeps foliage dry and discourages disease. The most critical stretch is the few weeks of head formation, when a single dry spell can ruin the crown. A 2–3 inch mulch of straw or compost steadies soil moisture and keeps roots cool, which matters most as the season warms toward harvest.

Recommended supplies

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