Well, I finally did it...overseeded the 10-month-old TTPR/KBG lawn with TTTF and KBG...and it worked! So it can be done...but read on to find out how I did it...I was quite careful due to what people on here had told me about the PR messing with the germination of other seed due to allelopathy. I did this a little over a month ago now. I actually prefer the lawn consisting of a mixture of these three species, guess I'm odd since no one else here seems to like that three-way mix). We're at ~4.5 weeks now. The existing PR thankfully did not prevent or delay germination of the new seed. The TTTF started to come up within 6 days, and was fully up in about 3 weeks time. The KBG just started coming up last week. Perhaps it wored so well because the PR was only 10 months old. Or b/c it got heat stressed. Or b/c I mowed it to ~1.8 inches before hand on the last mowing before starting the project. I also thinned the lawn fairly drastically prior to over seeding, by utilizing heavy core aeration (three passes) and also verticutting (two passes). I brought up a lot of dead and living grass in the process. I'm currently touching up the few spots that need it with a little extra seed. Here are some photos of the project (same area plus or minus a foot or two) at the various stages for reference (I do consider it a successful outcome even if it was my first time doing it and I learned a lot!): The top photo is the before photo, taken on 8/17/12. The middle photo is about ten days after overseeding, on 8/29/12. You can see the existing PR and KBG, and the TTTF was in the midst of germination, but is hard to see in the pic. And the bottom photo is from 9/21/12, taken right after the first mowing and application of starter fertilizer (I decided to hold off on the fertilizer until after germination so as to slow the growth of the existing grass to prevent it from overtaking the new grass. I'm glad I did this). Here is what I used for overseeding: -TTTF (approx 75% Firecracker LS and 25% Bullseye) -KBG (approx 33% each of America, Bewitched, and Rugby II) -A low amount of the existing TTPR seed blend (see below) was mixed with the fescue and KBG seed; I only used this in those areas that were really bare after the verticutting/raking. In this way, I created a uniform lawn in the bare spots that blended with the old grass. (The existing lawn prior to overseeding was a blend of KBG and three cultivars of TTPR sourced from from Allied Seed: ASP6005, ASP6002, and ASP 6001.)

I hate it when that happens. I had a reply in here and my browser crashed...badly - taking me all the way back to late June. But I'm back. I completely agree with tiemco on this. You have a much better than average lawn. I would spend the $20 on the Logan soil test and spend the rest on applying whatever they tell you. With a healthy stand of Kentucky bluegrass, the last thing you need is seed and the hassle of putting it down/watering/etc. Your color is a little off. I believe that is due to a lack of fertilizer. I don't know what your temps are but if the highs are below 85 then you have some options. If they are hitting 85 and above, then you have one option. If you are below 85 for an entire week at a time, then you could get away with applying ordinary synthetic fertilizer (slow release). Hot weather and salty fertilizers can put stress on a lawn so you need it to be cooler. However, if you are warmer, you can apply organic fertilizer any day of the year and expect good results. Here is a picture from mrmumbles he posted here in June. This was his organic fertilizer test. What he used was alfalfa pellets (Purina Rabbit Chow). Most people are skeptical of the modern grain theory of organic lawn care, but images like this are pretty striking. Note the color and density of his Zoysia lawn with and without the fertilizer. If you are intrigued by that image, go to the Gardenweb Organic Gardening Forum, find the FAQ, and read the last one titled, Organic Lawn Care FAQ. When I wrote that the price of corn was way down and soybean meal was high. Nowadays it is reversed (almost). In any case you get a large bang for your buck using soybean meal this summer. You can get it at most feed stores in 50-pound bags. The application rate is 20-30 pounds per 1,000 square feet of grass. I would definitely start at 20 pounds. When these fertilizers decompose on the lawn you will notice a different aroma. It doesn't stink exactly at the lower rates, but if you use 80 pounds THEN it stinks like sour milk. The more often you use it, the less you will notice the smell. This is because the soil microbes are becoming more populous and can deal with all the food you are giving them. The decomposition of food on the lawn is a biological process that takes a FULL three weeks to happen. You will not really see it coming either. In fact you'll be wondering whether the soybeans had any effect but then at the 3-week mark, it hits. I think when you see that, you will forget all about overseeding. And like I said you can apply organic fertilizer any day of the year. If you want you can apply it again in 3 or 4 weeks to get ahead of the neighbors. If they are using synthetic (like Scott's), they will have to wait until cooler temps to fertilize. There's a guy on another forum who has applied heavy doses of organics every week to speed up the process of improving his soil. It worked so well that his KGB lawn stayed green almost all winter. You might not be in that category of lawn nut but it is pretty easy to slip from simple hobbyist to complete lawnaholic when you see these kinds of results.

dense turf...ya gotta love it. andy, i did an overseed not a rennovation...i don't think i could go through the rennovation process without pulling my hair out. so rather than do what you did, my plan was to aggressively aerate and overseed with better quality KBG/TTPR every fall for three years. I'm hoping that this course of action will eventually transition 90% or more of my lawn to newer/better turf cultivars...this was year two...i'm doing the same in my backyard, except it's shady so I'm working with various fescues. anybody have thoughts on the best course of action to rid my lawn of bent grass(about 10%, in patches that are spread througout the lawn) I can't stand the way it looks or the way it lays down flat. I'm thinking that next spring I'll just start digging it out and replacing those areas with KBG sod(which might take many hours of work)...OR.. I've also thought about growing a few dozen little 3"x3" pieces of KBG sod in planters under a grow light in my basement next March and then once it's established, planting 3 or 4 of these little pieces right in the middle of each of these bent patches(this also would require some work but i'm thinking it might be kinda fun to grow some pure little patches of elite KBG this winter) anybody care to strategize w/ me on this one?

2K is so small that you'd be crazy not to nuke the whole thing and get the results you demand. IMHO, PGR use in overseeding is not helpful. what happens in 30 days when the effect wears off? ...rebound growth surge. if you reapply, it also stunts your seedlings which are probably strands of hair at that point. If you've never scalped a lawn--especially a thick lawn--you have no idea what you are in for. extremely difficult and time consuming. Have courage and just do it or youll just be doing it next year.