No maintenance landscaping (rocks?!) Chicago, IL!

[Edward Kuk]

Hi BiggerPocket community,

My wife and I purchased our first investment property 6 months ago in Chicago, IL. My goal for this property is to do small projects to reduce maintenance effort before we start looking for our next one. 

We gone through our first winter and things went thankfully smoothly! As summer is starting to hit, one project I have on my plate is to work on the garden. The previous owners (lived there for 30 years) put a lot of effort into the garden with lots of flowers. It looks really pretty but I have no intention to maintain. As sad as it is, I want to tear it all up and put something that will require no maintenance (like literally 0). Two questions:

1) I did some research and the one I'm thinking of is to dig up all the flowers and replace it with a bed of boring, but no maintenance rocks. Are there any other ideas people have done?

2) The front of the house also has a ton of flours and such. Can I replace this with rocks too? Do states have rules where you have to have grass or can I put put in a bunch of rocks so I don't have to deal with it?

Thanks for all your help!

Edward