Even if you missed harvesting your broccoli at the tight bud stage, it’s not too late to salvage something from the crop. It is possible to harvest broccoli even with the bright yellow flowers open.
Broccoli plants are designed to blossom and yield seeds. The ideal time to harvest broccoli heads is while the heads are still bright green and composed of tightly packed buds.
If some of the buds have turned yellow, it is too late, but there is some grace period to harvest the crown before yeasty froth turns it over.
That said, if you still haven’t harvested the bolts you can still make use of the plants. Tender portions of the broccoli plants include the stems, leaves, buds and flowers, all of which are edible.
Bright yellow broccoli flowers certainly qualify as edible flowers, some vendors even sell them as a niche high-end market food. Not everybody appreciates the taste though, as some consider it to be too bitter and grainy, whilst others describe the flavor as nutty and relish the unique textures the flowers provide.
The primary drawback to allowing broccoli to bolt is that the plant loses nearly all of its nutritional value after flowering. Eating the bolted broccoli is an option, but it will not provide the same healthy nutrition as traditional broccoli.
Nutrition-wise, broccoli blooms will not be beneficial. Regarding preparations, you can eat broccoli blooms either cooked or raw, but if you prefer them cooked, do not steam them, as that will lose the unique texture of broccoli flowers.