What requirements did settlers have to meet to keep their grant land?

Claimants were required to "improve" the plot by building a dwelling and cultivating the land.

The answer to the question: What requirements did settlers have to meet in order to keep their grant land, is: 1. they were required to pay a small fee, and 2. they needed to make their permanent residence in that land, with improvements on it, for the following 5 continouous years. If these two conditions were met, settlers were allowed to buy the public land from the government at a fixed rate of $1.25 per acre.

Explanation:

The Homestead Act of 1862, was signed into law by President Abraham Lincoln, and its purpose was to ensure migration and settlement of the lands in the west by American settlers. In order to encourage this migration and settlement, the new law set some terms and conditions under which settlers could acquire and settle public lands, and make them their property afterwards. But to do this, settlers had to first, pay a small filling fee, and then inhabit the acquired land for 5 consecutive years, and show improvements to it, before they could purchase it from the government at a very low price.