Welbeck, 19, set up the winner for Gabriel Obertan in United's 1-0 tour victory against Philadelphia Union last night and 20-year-old Cleverley was also thrown in from the start after scoring in the defeat of Celtic in Toronto last Friday.
Ferguson believes both players have bright futures at the club, but he wants to see how they get on in the top flight before throwing them in at the deep end.
He said: "This is going to be a big season for Danny because for the last three years he has not had a consistent run of games.
"I sent him to Preston as you know last year. He got an injury almost right away. He only played five games and ended up having an operation on his knee.
"One of the things about Danny that may have caused the injury is that he is still growing. He has a weakness in his legs with the speed he is growing.
"He is about 6ft 2ins and a bit now. He has sprouted up in the last year and a half. So he needs consistent football. He needs to play all the time and that is one of the reasons we are considering sending him on loan again to a premier division team."
Cleverley, meanwhile, was named Watford's player of the year.
Ferguson said: "Tom is a very talented boy. He is going to be a very good footballer. We are also considering putting him on loan to a Premier League team.
"He improved tremendously in his spell at Watford last year. He got an unfortunate injury towards the end of last season and was out for a long time.
"He has just come back and can play anywhere in midfield, which is always an advantage."
Cleverley is thrilled to be playing alongside Paul Scholes and Ryan Giggs and believes the two veterans can only help his development.
He said: "Last year was a big season for me and I hope this one will be even bigger. This time I have got to prove myself in the Premier League like I have done in the Championship and League One. That is the challenge for me.
"Playing for United and alongside someone like Scholesy is what every young lad dreams of. He is a great mentor for me - I look to him every day in training and he is definitely someone I can learn a lot from.
"The likes of Scholesy and Giggsy always have a picture in their heads about what they want to do with the ball and their first time passing is second to none. The way they go about training and matches means they are two of the best in the world to learn from.
"Being on the tour and among the first team has been fantastic. You are watching and learning from the experienced lads all the time and you try and hopefully put that into practice."