broccoli head
Updated: July 24, 2023

Planting broccoli facts

  • Hardiness: Hardy (can withstand heavy frosts in spring and fall). Biennial (a plant that requires two growing seasons to complete its life-cycle) but treated as an annual.
  • Planting: Start seeds indoors for early spring transplants. Plant seed in beds or flats for fall transplants or direct seed into the garden. Sprouting and raab broccoli are sown directly into the garden in spring. Follow seed packet directions for spacing. Full sun requires direct light at least 6 hours/day; prefers 8 - 10 hours/day.
  • Days to maturity: 55 - 65 from transplanting, longer for fall crop.
  • Spacing: 16”- 24” in-row x 24” - 30” between rows.
  • Fertilizer needs: High requirement for nutrients, either from soil organic matter or fertilizers. Use starter fertilizer when transplanting; side-dress three weeks later and when central head has been cut to encourage side shoots to produce additional small heads. Refer to Fertilizing Vegetables for details.
  • Approximate yield (per 10-foot row): 4 to 6 lbs

Broccoli problems

Bolting
Cabbage looper
Flea beetles
Harlequin bug
Imported cabbageworm

Growing and care of broccoli 

  • Broccoli (from the Italian plural of broccolo, refers to "the flowering top of a cabbage") is a plant of the cabbage family, Brassicaceae.
  • There are four types of broccoli: heading, Romanesco, sprouting, and raab.
  • The heading type, which is closely related to cauliflower, forms a large central head. The heads of broccoli are really flower buds that must be harvested before the flowers open or show yellow. Mature heads measure 3 to 8 inches across. Smaller, lateral heads develop after the central head is cut.
  • The spiraling heads of Romanesco broccoli are quite dramatic.
  • Sprouting or Italian broccoli forms many florets or small heads, but do not produce a solid head. Broccoli raab is not a true broccoli but a type of turnip (Brassica rapa) cultivated for its flower head.
  • Broccoli is planted in spring for June/July harvest and in summer for a fall harvest.
  • Five to seven-week-old transplants are set out four weeks prior to the last frost date in spring. Temperatures below 45°F may inhibit heading or encourage seed stalk formation (bolting). Transplants for fall planting can be produced along with cabbage and cauliflower transplants, taking about 4 to 6 weeks from seeding to setting into the garden. Seeds can be sown directly in mid-July for a fall harvest or transplants are set out by the first week in August.
  • Fall broccoli often produces higher yields than spring plantings in the mid-Atlantic region. 
  • Watering - Keep the root zone moist by watering deeply and regularly during dry periods.  Water more frequently when heads begin to develop.
  • Weeding - Broccoli has a relatively shallow, fibrous rooting system. Cultivate carefully or use a thick mulch to prevent weeds.

Harvesting broccoli

  • Cut the central head (large terminal bud cluster) before flowers open, then cut small side bud clusters as flowers develop over the following weeks. Harvest with 6 to 8 inches of stalk.  

Storage and preservation 

  • Store in very cold (32 degrees F), moist (95% RH) conditions, 10 to 14 days. Broccoli can be blanched and frozen.

Additional information

Beyond Broccoli: A Brassica Series | Maryland Grows Blog

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