The Colombian international signed for the 'Cherries' for £25m this summer and could feature for the first time in a Bournemouth shirt against Everton on Saturday.
Lerma managed 90 minutes for Bournemouth's U21 team on Tuesday against Brentford, with Howe impressed with his performance.
"It was nice, I thought he did really well.
"His attitude to the game was first class, his fitness levels looked very good so I was very pleased with his performance, as I was with everyone who played
The manager said "You'll have to wait and see" in response to whether Lerma will start against the 'Toffees'.
Howe was also impressed with Everton's start to the season: "I think Marco's done well with the team that he's inherited.
"You can see that their implementing new things and doing that really well."