75-80 days. In our winter trials this green brokali pumped out a truly impressive amount of big stemmed broccoli-type spears. Proper harvesting of Endeavour is the key to its long harvest window. Cut the main head when it reaches the size of a ping pong ball. Once the main stem is cut, the side stems will start growing lower on the plant. When these side stems reach 4-7 inches long, it's time for them to be harvested. This process repeats further and further down the plant for about 2 months. You'll find the flavor sweeter than normal broccoli.