What is the soil this lawn is trying to grow in like? What is the soils pH? What kind of life is in the soil? How much organic matter is in that soil?

Corn Gluten Meal inhibits a plants ability to establish roots so spreading CGM to control unwanted plant growth while spreading seeds to establish wanted plant growth is an exercise in futility.

Getting the soil into a good condition to grow the plants you want is essential to growing those plants and these simple soil tests may be of some help along with a good reliable soil test for pH and major nutrients.

1) Soil test for organic
material. From that soil sample put enough of the rest to make a 4 inch level in
a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and
replace the lid, tightly. Shake the jar vigorously and then let it stand for 24
hours. Your soil will settle out according to soil particle size and weight.
For example, a good loam will have about 1-3/4 inch (about 45%) of sand on the
bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above
that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole
1 foot square and 1 foot deep and fill that with water. After that water drains
away refill the hole with more water and time how long it takes that to drain
away. Anything less than 2 hours and your soil drains’ too quickly and needs
more organic matter to slow that drainage down. Anything over 6 hours and the
soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful
of your slightly damp soil and squeeze it tightly. When the pressure is
released the soil should hold together in that clump, but when poked with a
finger that clump should fall apart.

4) Smell. What does your
soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant
odor? The more organic matter in your soil the more active the soil bacteria
will be and the nicer your soil will smell, to a point. Too much organic matter
can be bad as well.

5) Life. How many
earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5,
according to the Natural Resources Conservation Service, indicates a soil that
is not healthy.

kimmq is kimmsr

Thanks!

The soil is clay, ph is 6.7, organics are at 10%. A recent extension service soil test showed excessive P, K, Ca, and Mg. Here's the report:

I'll take a look at the other tests, they seem like good stuff. I have done the test for salts where you drop a soil ball into a jar of water and see what happens: it made me sure I don't need gypsum!

Not a formal test, but the kids have no problem finding earthworms. And the soil smell is much improved for adding a few truck loads of compost of the past few years to the 8k sqft lawn. I'll check tillage and draining when I get a chance.

BTW, we are forecast for a big snow in a few days. Rolling the dice with dormant overseeding is worth a try, with the obvious caveat that I'm at the mercy of the weather. But trying something different makes sense. For seeding and overseeding too close to October 1 these past two years, I have had serious germination problems. I think given the widespread shade on this lawn, fall seeding needs to be closer to September 1, but for now I'll just try this!

Corn gluten meal doesn't work well enough for you to worry too much about it stopping your grass from germing. The grass will also probably be off & running before the temps got high enough for an appropriate CGM application anyway. Crabgrass prevention in organic lawns is basically just elbow grease... Pulling it & preventing the compacted conditions that favor it MAY help in conjunction with the CGM, but I'm still skeptical. Its a tough plant.

Thanks for the info about CGM. I'd thought that the grass germination might come first and that I could get some CGM to stop later crabgrass. The more research I've done on both organic and non-organic methods of crabgrass control the more I've realized that it is in fact a tough plant and that getting the lawn into better shape is best way to focus my energy. I also found out that the neighbor with the really weedy lawn has been partial to CGM as well! And a lot of crabgrass density is just a function of each years' conditions.