Number one, get the soil prep right. I have seen many, many people take a tractor and scrapeblade to smooth out a lawn for seeding. Every pass that the tractor makes just compacts the soil more and more. Once the lot is level and the finish grade work is done, take a tiller and till it up to break the compaction, hand rake smooth and then use your brillion drill. When using the brillion, go in at least two different directions at an angle to the first pass, sort of like ###. This will help eliminate the corn row look of the seed spacing and also insure more even coverage.
Number 2, Choose the right seed, in Mn, I will assume maybe a turf type Rye grass, Kentucky blue grass, or maybe even Bentgrass, Possibly some fine fescues. You can go to the NTEP.Org website and find a specific varitity of turf grass that will do better in your area. Reccomended seed rates are often over stated, this is simply because most folk buy the seed dont have a clue as how to plant it properly. With fescue type grasses there is over 200,000 seeds per lb of seed. Now this isnt all live seed and also isnt completely free of weeds, but there is a tag on ever seed bag that tells you how much live seed to expect and how much weed seed might be present. There is 144 sq inches in a sqft and 144,000 sqinches in a 1000 sq ft. One lb of pure live seed per 1000 sqft will result in over 1 grass plant per every square inch of your lawn recomemded seed rate can be as much as 8lbs per 1000 sq ft for fescue grasses. Some will die simply because of over crowding. If the grass is properly planted and properly cared for, you can get by with 25lbs of seed per acre. If you dont think you can do everything I just wrote, go with the heavy seed rates. Seed rates will be lower for Kentucky blue grass and bent grass, and rye will be about the same as the fescues.
Number three, soil fertility should be addressed before the final till and rake, not when planting the seed.. Soil test the soil and apply the proper nutrients at the proper rates and incorporate into the soil while tilling. Fertilizer is not neccessary at planting, the seed cant use it until after it germinate. Fertilizer is a salt and actually hinder's seed germination. High nitrogen fertilizers, especialy Urea based nitrogen, when applied with the seed at planting, can result in killing off 50% of the seed in the first 24hrs after application. All it takes is a little heat and moisture and the urea will convert to ammonium gas and create a dead zone around your just planted seed. If you are going to use a urea fertilizer, till it into the soil at least one day before planting your seed. If you must broadcast the fertilizer ontop, water it in deeply to reduce the gasification and lost of nitrogen to the atmosphere.
Number four. Irrigation is crucial, especially during the hot dry summer months. If you cannot irrigate properly, then you are better off not to irrigate at all. Improper irrigation will cause the seed to germinate and then die off due to lack of water. Once the seed germinate and dies, its overwith, it wont come back and it wont fill in and you will have to start all over. Not all seed germinates at the same time, its completely controlled by the amount of moisture present.
Over watering is just as bad as under watering. To much moisture creates humidity and can result in fungal problems and damping off of the seed. Double true if to much nitrogen is used. Fungus loves nitrogen and just a little bit of nitrogen can cause the fungus to completely overtake the lawn. Cool season grasses do better if planted in the fall, 1st, and the spring, 2nd, best time to plant. Its cooler and humdity levels are usually lower.
Number 6, resist the temptation to fertilize during the summer months on cool season grasses. Cool season grasses will go dormant during periods of hot dry spells. Fertilizing when the grass is dormant only fertilizes the weeds and is a just a waste of time and money.
Number 5. Mowing at the proper height. The first mowing should take place when the new grass is at your desire mowing height, the height you intend to keep your grass cut at once established. Let the soil dry before mowing to reduce the chance of rutting from the mower wheels. Cool season grasses generally should be mowed at least 3 inchs and never any shorter than 2 inches.(exception would be bentgrass) Short grass results in short roots, making the turf more succeptable to drought situations. Mowing to tall will result in wide bladed grass blades and clumping while being cut. Always make sure the mower blades are sharp, especially for the first cut of your new grass. This reduces the white tips of the top of freshly cut grass and also helps prevent the new grass from being pulled out by the roots by the dull blades.
