Seeding vs Sod

can you live with the trashy grasses which the blue will NOT crowd out?
If SO kill the weeds and rent a slitseeder to PROPERLY set the seed in the soil (MUST have soil/seed contact to germinate, scattering seed will result in less than 10% germination). No need to STRAW (DON'T use hay!!)
If NOT, spray whole lawn with roundup (or similar) to kill everything, then rent a slitseeder to properly set the seed. They rent for about $100 a day and you'll need 18lbs of seed for overseeding (existing turf) or 30lbs if you kill it all. Apply starter fert at the time of seeding and it will fill in MUCH better.
Blue grass requires THIRTY-THIRTY FIVE days of CONSTANT moisture to germinate! Rye (in blends) is what sprouts in two weeks. Stop watering then and you'll get NO bluegrass! Water twice a day at least, if it's dry on top when you come out for the next watering then you must increase the time or frequency. Seed MUST not dry out after it's gotten wet, or it's DEAD.

I've decided to round-up the yard first, probably this week, wait 2 weeks and do it again. I'm trying to shoot for seeding by September which I'm hoping will coincide with the lifting of watering restrictions here in Denver.

A slitseeder- is this a walk behind item? Never heard of it, rental places carry something like this?

Hay and Straw are two different things? Where do you get straw? I was just going to go to a horse feed supply to get the hay.

Starter fertilizer sounds like something I should do, any recommendations? I'm not a pro so I don't have the knowledge or the access to most of the stuff you guys use, just Home Depots or the local nursery.

What about the dead turf that will be there by September? What do you recommend to do with it? Just rake up what comes up, or rent a tiller and till it in?

Thanks,

Yes, a slitseeder is a walk behind. Usually a Ryan Mataway is what the rental yards carry. It uses a reel cutter to slice slits in the dead turf and then drops the seed into those cuts. The seed comes up in straight lines and fills in from there.
You use a slitseeder so you don't have to get rid of the old turf. Tilling is the LAST thing you want to do. Say about 50 times more work raking all the turf pieces out.
Hay is the growing part of the plant that has all the nutrients. You feed it to animals. It's also full of weeds since it is a fresh product. Straw is the empty hulls and stems of the plant. Dried and less weeds, though usually plenty anyway. Another reason to slit seed as the old turf acts as the cover and helps keep the seed wet, without adding weed seeds.
I use 12-12-12 or 19-19-19 for starter fert. Doesn't matter, you're just giving it a hit to get it growing faster. It's less than $10 a bag too. There is expensive slow release stuff if you want to pay more.

You do not need straw unless there are significant bare spots. After Roundup, when the existing plants are dead, mow the lawn as short as possible without scalping - should be able to mow down to 1½" at least. This dead stubble then works as your mulch and soil stabilizer - that is why you need no straw, except for bare dirt areas.

Gotta disagree some with Mike B on the seeding and germination of KBG. After mowing, if you can core aerate (another machine to rent) at least 3 passes over the whole lawn, then you will only need about 4# of pure KGB seed per 1000 ft ² (providing that label germination rate of your seed is at least 90%). If you are only slit seeding, without aeration, use 4.5# to 5# per 1000 ft². Run the slit seeder to apply seed at half the rate desired, and make passes in two directions, to form diamond shaped cuts across the lawn. This is to mask the lines of new seedlings for the first fall growth - with lines in two directions, they do not stand out so much.

And if you can irrigate after seeding, give the lawn a good soaking watering first. Then apply a max of 1/10" of water twice a day - early morning and mid afternoon - usually just 8-10 minutes each time with most hose type lawn sprinklers. If you have an irrigation system, small popups sprays only 4-5 min, gear heads about 15 min. Out there you may even get a third watering in on clear days. The object is to repeatedly wet the seed, to speed germination. But if you keep the surface soaked, you will rot the seed. Here I can get 2 waterings a day in Aug to mid- Sept, and I usually see germination start by day 6, with a full green fuzz by day 10, on pure KBG plantings.

Wow, you guys know your stuff.

I'm still confused as to where you buy straw versus hay?

As for the seed, I've been looking here http://www.seedland.com/cgi-bin/miv...een=CTGY&Store_Code=Seedland&Category_Code=BG at seedland.

They have way more selections than I ever knew existed. Does anyone have any advice in regard to the seed to purchase.

Should I be getting a blend of Kentucky bluegrass/Rye/Fescue or a pure Kentucky bluegrass seed only?

Is there any such thing as a pure bluegrass lawn or this something never done? They have something called Midnight#1 which seems to be the Cadilac of bluegrass seed, but I'm way over my head here. Are you just asking for trouble with such a high end lawn seed?

Sorry, Mike - I just glanced at your numbers and they seemed high. Normal rate for a new seeding, on tilled soil, is 3# per K. Overseeding rate is usually stated at half that. My numbers were based on slit seeding into dead stubble: slit seeding only => @65% successful germination; with multiple coring passes, you can get up to 75-80%. And yes, I consistently get KGB germination in 7 days with the method stated above. That is late summer seeding, would expect a couple of weeks or more in spring. But if I sed in spring, I'll do rye, then kill it off in Aug and slit seed all blue.

Mfinley, you never plant just one variety of any type of grass. A pure KGB lawn should be at least three, preferably four different KGB varieties. A knowledgeable local seed supplier should be able to help there. And don't go cheap. I would not recommend varieties for your location, because success with a single variety varies all over the country.

If you use a blend, and the blend contains more that 10-15% ryegrass, you will have basically no bluegrass survive; the rye germinates so quickly and grows so aggressively it will not allow the later germinating bluegrass to survive.