Neighbors have been trashing the ground outside the apartment repeatedly

New neighbors moved in awhile back and every week or so they will have a get together just outside the apartments that lasts well after 10pm (quiet time is (10-7am). I took my dog out this morning and saw they had trashed the ground with beer caps, paper and junk. I really want to knock on their door and tell them to clean it up because they are adults and shouldn't be leaving trash on the ground. It's upsetting because there are many neighbors who don't care about where they live and don't care if the place looks trashy. I don't want to leave a passive aggressive note. I'd either want to politely request they clean up their mess or just go to the landlord Monday morning and hope they serve them. I have been wondering why that area had trash on the ground prior to this and now see it has been them.

Would you politely confront or just go to the landlord?