I’ve grown broccoli for the last two years and all I get are huge plants with either little or no flower heads. What seems to be the problem?

Timing is key!! Broccoli likes to stay cool.

Causes of no or poor flower heading:

• Alternating periods of abnormal high temperatures followed by abnormal low temperatures stresses the plant  and causes heading to come to a complete halt.
• Stress brought on by drought or inadequate moisture.
• Excessive nitrogen can cause huge healthy plants with little or no head production.
• Transplanting too late with root bound plants will keep the broccoli from heading.
• Transplants when exposed to temperature of 40 degrees and below for 1 – 2 weeks triggers heads to form too early or not at all.
• Transplants not properly hardened off will be stressed and perform poorly. http://papasgardens.com/2015/04/24/what-does-it-mean-to-harden-off-seedlings/
• Overcrowding results in either little or no head formation due to competition for adequate water and nutrient.

Prevention:

• Proper timing of transplanting for your specific area. Your County Cooperative Extension Service will supply the dates for planting.
• Proper planting of transplants 2 feet apart.
• Even supply of moisture. Drip irrigation is best.
• Balanced nutrition/fertilization. Avoid excessive applications of nitrogen.
• Proper hardening off of transplants.
• Cover planting when temperatures drop below 50 degrees. Low tunnels with floating row cover or cloches will provide protection. 
• Plant in Fall.
  • Decreased pest pressure.
  • Plants are usually stronger. The flower heads are bigger.
  • Plants grow better into cooler weather.
  • Sow seeds for transplants 10 – 12 weeks before first frost.
  • Set transplants 2 feet apart for extended season planting.

Broccoli are sensitive to their environment. When treated with care, they will reward you!

Papa