Picture: Bluegrass seedlings

The first question that must be answered is are you overseeding your lawn or "starting from scratch"?  A decision must be made to either plant within an existing lawn or to till up your lawn area so that no weeds or grasses are left living in the area to be planted. Of course a new lawn planting will most likely be started with the ideal situation.  That is to have tilled soil for the area where you will establish a lawn grass from seed. 

Why Ideal?  Because existing plants that are directly next to (6 inches or closer) of where you are trying to establish other grass plants from seed, provide competition to your seeds by consuming sunlight & plant nutrients.  This competition by existing plants means some plants simply won't survive the additional stress imposed by these adult plants.   Also, eliminating the existing "old" grasses, means that you will be able to establish the proper mix ratio and variety types for your new cool season lawn.

Bluegrass lawn  maintenance   Helps to deter  loss of plant material. But thinning  coverage can be due to many reasons. Climate being one of the main culprits. Overseeding one of the easiest methods to correct this problem. Cutting small sections of sod  may be an option for smaller areas.

First: Decide if you will till the soil (So as to kill all the existing plants by plowing up your site!) or just plant within the existing grass. Also decide on the variety of Bluegrass to plant.  And if you will plant a mixture of Bluegrass with other lawn grasses such as RED Fescue & Ryegrass.  This (3 way mixture) is often used in spring plantings of a mixed Bluegrass lawn.

I will TILL my site and start Fresh! I will NOT TILL my site - I want to overseed my existing lawn.

You are not tilling the soil - and are planting seeds within the existing grass & weeds;

OVERSEEDING - Note: Bluegrass may have thin spots over time, so overseeding helps to thicken the turf in those areas to achieve higher plant density.

(1) Mow your lawn as close as possible and remove the excess clippings with an iron-rake that will also scratch your site soil, preparing a home for the seed. 

(2) Next if at all possible AERATE your lawn with a spike aerator.  Planting without aerating does not allow of good soil contact of your Bluegrass seed.  Aerate by traveling first North to South and then East to West (two trips across lawn). Then sow (broadcast) your Bluegrass seeds on the area to be planted generally in the early fall (Aug - Sept) for your best results. Spring (before May) seedings can also be done with Bluegrass.  Some people say they find overseeding both spring and fall works best for them. 

However you may also seed in late fall at the same time you use a cover crop such as ryegrass.   The Bluegrass seed will start germinating the following spring provided that snow and/or low temperature conditions have protected the seeds until spring germination.  Timing is important depending of if you are in a more Northern cool-season area or in the transition zone.

(3) After you have broadcast your seed, you should aerate a third time.  This last time helps to provide soil coverage of your seeds.  

You may also Roll the area sowed with a hand roller so that the seed that you sowed, which fell into the soil scratches made with the rake, will become firmly packed with the soil.  Bluegrass seed require firm soil contact for best germination.  They also need a thin soil covering to germinate (1/4 inch ideal) - They are not likely to germinate when thrown out on top of the ground, unless a mulch covering or top soil is applied.  Use the correct rate of seed for Bluegrass lawns.

(4) Follow your normal water, fertilizing and mowing practices for the area you have planted on a regular basis.  That's all!  Eventually you will have an improved, more lush and thick Bluegrass grass lawn.  Bluegrass seeds do take longer to germinate (often 4-8 weeks), thus many landscapers also include perennial ryegrass as part of their turf establishment.  Generally you should water daily after planting until germination occurs, then continue on a more normal cycle. - www.lawnirrigation.com 

Keep in mind that if overseeding a NEW lawn you need to create a good firm seedbed (soil) for your seedlings to grown in. Using a tiller is the best preparatory method.  A second method is to use a rake to loosen the soil and make for better germination of your grass seed.

Visit our www.lawngrasses.com for more about seeding rates and lawn choices for grasses. For pasture seeding the rate is normally lower.   Keep in mind that the seeding rate is purposely higher for lawns so that the higher plant density needed for lush turfgrass lawns is achieved.

Planting on correctly prepared and tilled soil.

(1) Till the area to be planted.  Early fall is the best time to start this activity for Bluegrass. The tilling can be done with either a garden roto-tiller or a tractor harrow/tiller (Or even a shovel if you have a good back!).  Once the area is properly returned to soil, level the ground by raking or dragging something over the surface until it is smooth and level.  Now is the time to remove hills and depressions so that you have a nice smooth lawn.

(2) Plant your seeds.  You can use a commercial turfgrass planter or sow the seeds by hand, or just as easy and much preferred, buy a broadcast seeder  (hand held and push models are available for $8-100).  Once your seeds are sowed, rake or drag the seeded area, so that as many of the seeds as possible are lightly covered (1/4 inch is ideal covering). Be sure and use the correct rate for seeding Bluegrass.

(3) Water the area you have planted as needed.  Generally water every day until germination occurs, then return to a regular watering schedule.  Apply fertilizer in intervals through the growing season, and practice a regular mowing schedule.  Mowing the weeds that will grow in your new lawn area faster than the grass, allows the grass to compete better for scarce nutrients and sunlight. - Mow regular and at the correct height.  Bluegrass seeds do take longer to germinate (often 4-8 weeks), thus many landscapers also include perennial ryegrass as part of their turf establishment.  

Visit our www.lawngrasses.com for more about seeding rates and lawn choices for grasses. For pasture seeding the rate is normally lower.   Keep in mind that the seeding rate is purposely higher for lawns so that the higher plant density needed for lush turfgrass lawns is achieved.

Your lawn will grow to be beautiful over time! 
If you can't wait..... consider SODDING