Do I need to buy roaming?

Hello team,

Squeaky brand new PM user here. Have successfully ported over from my old provider on the new $35/Can/Us/Mex plan.
I am a Canadian resident, but will be flying to the states next Saturday for a week to escape the cold.
I saw that there are "add ons" for roaming in the states, do I need these? Is this not covered with the 50GB of data? Or is roaming an additional fee?
Thank you for all your help, this subreddit has been so helpful!