Why are white asparagus spears often thicker and more tender than green spears at harvest time?

They are harvested earlier and kept protected, resulting in less tough fiber development

The physical structure and texture of white asparagus differ from green asparagus largely due to its protected growing cycle. Because white asparagus is continuously covered to prevent sunlight exposure, it is typically harvested at an earlier stage of development compared to green stalks that mature above ground. This early harvesting, combined with the protection from elements that encourage toughness, means that the spears develop less rigid, tough fiber. Consequently, consumers often find that white asparagus spears possess a naturally more tender texture compared to the more robust structure of sun-ripened green spears of a similar diameter.