You can change the default “Search this Website…” text in the Search bar field in a Genesis WordPress theme by using a filter added to your functions.php file.

genesis-search-text

//Change search form text

function themeprefix_search_button_text( $text ) {
return ( 'Search text goes here...');
}
add_filter( 'genesis_search_text', 'themeprefix_search_button_text' );

So in the above code a  function is created, the text is passed in as an argument and run against the Genesis filter genesis_search_text .

genesis-search-text-default