I should add that I live in NJ, so I am looking for a cool season grass. I think I wouldn't be so unhappy with my blended grass if I could get it to fill in the bare spots on its own....at least some of the time.

hey Rutgers1,

Just to keep it clear. A mix is what you really mean. A mix is made up of different grasses (say KBG and rye).

A blend is actually one type of grass with a mix of different type cultivars within that type. (Say three types of KBG or three times of Rye).

Rye grass doesn't spread. (Auteck makes the point that it can thicken by tillering. But it will not fill in bald spots.)

Based on your existing lawn, your best choice is problably to seed more KBG. It spreads and will fill in bald spots.

However, if, like Auteck, you prefer rye. You could just commit to yearly or every other year seeding of the rye grass.

There are also a few newer type Turf-type tall fescue's that spread. But I wouldn't suggest adding them to your rye/KBG lawn.

There are some other fescues like creeping red fescue that will spread too. But I'm not sure how suitable they would be for your location (shade, etc).

But I still believe that your best bet is KBG, especially if you live in or near Middlesex County.

Are the bad spots in shade, too dry, too wet, or any other stressful situation? KBG will spread if conditions are favorable, but it won't "fill in" well unless the spot is well suited to KBG.

Creeping bent.
Not a grass to mix with other species.

Rutgers1,

Bill is correct (as always). You need to tell us what conditions the bald spots are in. KBG isn't a great choice for shade.

Most of the little bald spots are in the sun. I don't think water is an issue, as I have a sprinkler system and put down an inch or so a week.

Thanks for the feedback!

KBG fills in, but we are talking about filling in 2-3" spots in a year - even under favorable conditions. If your ground is hard or compacted, it will be slower. It you have other grasses mixed in, it will be slower still or may not happen at all if you don't have enough KBG in the immediate area. If you want to increase the amount of KBG in the mix, you can aerate and overseed this fall.

Of course, if you have a big dog or kids who are tearing up these spots, no amount of spreading grass will keep up with them. In that case, you may as well plan on overseeding each fall to keep it thick and looking great.

I use a patch of KBG turf from a less conspicuous part of the lawn. Scratch up the bare spot, lay some compost under and around the "patch" water it from a sprinkler can every day for a week or so. This fall, I am planting a nursery plot of KBG in the back yard for larger sod pieces.

+1 Everybody

KGB hands down for where you are for its stronger recuperative powers and enjoyment of bright sun. Overseeding in fall and/or patching the spots with small pieces of sod (in whatever month as long as it's not late fall or winter) will work well.

KBG fills in, but we are talking about filling in 2-3" spots in a year - even under favorable conditions.

Roundly true. In a given worn spot, not all the grass usually dies. Plus you get spreading from each point on the outside of the circle inwards.

Somehow I managed to get a two foot incursion of bluegrass in two months (far exceeding the 3" per year given). I think I had more in the middle than I thought. Plus I have to cut six inches away from the gardens twice a year. The ground there tends to stay damper and cooler, and it gets fed very regularly from whatever runs off the gardens.

Treat a worn spot well (keep it watered, fed, and as protected as possible) and you can get tillering far beyond the average and well into optimal territory.