Can you still eat bok choy or choy sum after they have flowered?

Generally speaking, whether flowering Chinese cabbage (choy sum) is still edible depends on its specific condition. The details are as follows:

If the choy sum has only just begun to form a few flower buds, with no obvious fibrous toughening of the stem, and the leaves remain green, fresh, and free from yellowing or wilting, and if the texture feels tender without any off-odors or soft rot, it indicates that the vegetable has not over-aged and can be safely consumed. Before cooking, remove the flower buds and trim off any tougher portions of the stem. Although the texture may be slightly inferior compared to non-flowering choy sum, it remains safe to eat and still provides nutritional value.

If the choy sum has bloomed extensively, with thick, heavily fibrous stems, yellowed or wilted leaves, or shows signs of unpleasant odor or soft decay, this indicates significant aging or spoilage, making it unsuitable for consumption. Such choy sum not only has a coarse and tough texture that is difficult to chew but also suffers from substantial nutrient loss. Eating it may increase digestive strain and potentially cause gastrointestinal discomfort.

When selecting choy sum, choose specimens without flowers, with bright green leaves and tender stalks. Consume them promptly after purchase to avoid prolonged storage that leads to flowering and aging. If the choy sum has already flowered, carefully inspect its condition—when in doubt, it's best not to eat it, ensuring both food safety and optimal taste.