Tenant's landscaping work requiring landlord's permission?

[Jacky Johnson]

Hi. I have a tenant who has been renting several years in my property. I was doing gardening work for him today and he mentioned that he wanted to pave grass in the backyard and plant scrubs in the front yard. He did an estimate for the pave grass job and showed me pictures of how he planned to plant the scrubs in the front yard. Does he need my permission to do this kind of landscaping work? If not, what kind of landscaping work does tenant need the landlord's permission to do? Thanks.