Final answer:
The inability to grow their own food significantly impacted Jamestown settlers, leading to famine and high mortality rates. The introduction of tobacco farming later stabilized the settlement and led to its eventual success as the first permanent English colony in North America.
Step-by-step explanation:
The aspect of the Jamestown settlement that most directly affected colonists during its first years was the settlers' inability to grow their own food, which led to famine and a high mortality rate. The colonists, largely gentlemen and tradesmen lacking agricultural skills, initially focused on finding gold and neglected farming. This, combined with poor health, bad weather, and conflicts with the Native Powhatan tribe, led to many deaths during the first years, particularly during "the starving time" in the winter of 1609-1610.
It was only with the arrival of new supplies and settlers, along with the cultivation of tobacco as a cash crop by John Rolfe, that the colony began to stabilize. The introduction of tobacco farming also initiated a shift towards a plantation system and the eventual reliance on the slave trade for labor. Despite these early struggles, Jamestown was the first permanent English settlement in North America and laid the foundation for future English colonization.