I figured it out!

To make it multiline use the edittype textarea, set the number of rows in the editoptions.

To change the width of the textarea, set the number of columns (cols) in the editoptions.

$grid->setColProperty(“RiskDescr”, array(“label”=>”Risk Description”, “width”=>235, “edittype”=>”textarea”, “editoptions”=>array(“rows”=>5, “cols”=>100, “placeholder”=>”– Enter a Risk Description –”), “editrules”=>array(“required”=>true), “searchoptions”=>array(“sopt”=>array(“cn”))));