Natural edging beds on a bremuda lawn

[NickN]

I have a question for you guys that use no flower bed edging material,just the natural cut edge.No one down here does this,until now.
A gentleman in a subdivision I work in moved here from Iowa.Nice looking home,had bermuda installed last year and created his own beds with natural edging.He's done all the right things and it's apparent he enjoys working in his lawn.It really is a work of art.BUT,I'm foreseeing a problem here.I know from experience that bermuda can and will run like crazy when the temps warm up.By the end of summer I'm picturing bermuda in all of his flower beds.Heck,I've seen it run under edging into beds and sprout up.
I thought about bringing this to his attention,even though he is no customer of mine.Just a friendly word of advice.I'm wondering though,if he knows something I don't.What do you guys think?Bermuda in the beds by summers end or do you think he can keep it out?

 

[Bama1]

He can keep it out. I do not have any border around the beds on my accounts. Each week, I use my stick edger and "trace" the bed lines with it. This keeps the grass from crawling into the beds and gives it a fresh clen look!!