Flowers are necessary for fruit, but not for plants in general. Plants and algae and fungi existed long long before flowers evolved. You can still rely on leave

Flowers are necessary for fruit, but not for plants in general. Plants and algae and fungi existed long long before flowers evolved. You can still rely on leaves (spinach, lettuce, chard, etc), roots/tubers (yams, potatoes, carrots, etc), stems (celery, asparagus, bamboo, etc), and many other parts. Not to mention the majority of lichen are edible and the many many edible mushroom species. Also edible algae and seaweeds