Aarons, 24, joins on a deal until the end of the season and will help replace James Scott, who has signed for Hull City.
The former England under-20 international spent the first half of the season on loan at League One promotion chasers Wycombe Wanderers, scoring twice in 13 appearances.
"We're delighted to be bringing in Rolando," said Well manager Stephen Robinson. "He will bring even more pace and energy to our front line and give us options."
"His arrival will also allow us to move Mikael Ndjoli into his more natural position as a central striker, instead of playing in wide positions."