[mmicha]

I grew up with a sodded yard in the Chicago suburbs. As far as I know it was Kentucky Blue Grass. It seems sod in this area is all one type or another.

I love the look of it, feel, etc, but it seems like most seeds I see are a blend of a couple cultivars for this area. Usually KBG, PR, and Chewing Fescue.

If I was going to seed, is the idea of having a 100% bluegrass lawn a suicide mission? Even if it is a few different cultivars? Do those other grass types stick around or are they there for ascetics early on and get overgrown by the bluegrass?

Thanks!

 

[chrismar]

If you do a reno (kill and seed) you can have a 100% KBG lawn. Many of us here have done just that and have happy, healthy KBG lawns. You're not likely to ever end up with a 100% KBG lawn If you're planning to overseed your existing northern mix with just KBG.

 

[g-man]

To add to chrismar, most kbg overseed are a failure. Not enough time to establish.

 

[Green]

If you're old enough (older than me) the sod in your area might have had Merion Kentucky Bluegrass.

A KBG-only seed or sod blend (not a mix!) with Midnight KBG might be a good alternative in today's world. I doubt you'll be happy with anything else given how you grew up...

To answer your other question, mixes are semi permanent or permanent. Tall Fescue will live just as long as Kentucky Bluegrass. Ryegrass might even overtake KBG during the first few years, but after 20+ years (just making up a big number), it might die out for various reasons. Fine Fescue will also last forever, and will overtake KBG to a degree if the lawn isn't fertilized much for years or has shade.