Why do your broccoli plants have yellow flowers?

Broccoli plants develop yellow flowers when they bolt, which is a natural response to stress factors such as high temperatures, drought, or insufficient nutrients. Bolting is the plant's way of reproducing before it dies, leading to the formation of flowers and seeds. To prevent this, it's important to provide consistent watering, adequate nutrients, and protect the plants from extreme temperatures. If the flowers appear, they are often a sign that the broccoli is past its prime for harvesting.