Lawn needs some help, thinking about going organic
I've got about 7,000 sq. ft. of lawn in central PA (Zone 6) that needs some help, and I'm thinking about going organic as well. Looking for some advice on a plan of attack for my various issues.
First, description of the lawn. Standard subdivision lot, 1/4 acre with 2-story house and driveway. The house faces NNW, but there is a small section of very tall mature trees between my back yard and my backyard neighbors, so the back yard doesn't get full sun like you'd expect with southern exposure. The N (front) and W side get more sun than shade, and the E side is probably 30-40% sun, all morning. The entire lawn seems to be a standard northern KBG/rye/fescue blend. The front yard is in the best shape: some thin areas, some dead/bare spots (a dozen or so, mainly along the sidewalk, I suspect from the neighborhood dogs... although our dog pees all over the yard and doesn't kill anything), but mostly average thickness green grass that grows pretty well. The W side is pretty thin, and looks like it has been patched several times in different areas with different varieties of grass. The E side is also thinner and on a fairly steep slope (a full story since we have a walk-out basement which walks out the back of the house at the E corner). The back yard is in the worst shape: very thin, uneven/bumpy, quite a bit of moss. Along the back edge of the back yard where it meets the trees is basically just bare dirt -- once the trees have leaves it's full shade along this back edge, although the closer to the house you get the more sun there is.
Now, what I've done so far. We moved into the house in late November 2013 (after Thanksgiving), so I didn't have a chance to do any fall work on the lawn. Once things finally started to warm up in early April I had a soil test done (Penn State AASL), which came back with pH 6.5, Phosphorus 18ppm, Potassium 48ppm. Recommended no lime and 3-4 applications/year of an 18-6-6 fertilizer at 5.5 lbs/1000 sq. ft. Closest I could find was a 19-5-5 at the local John Deere Landscapes, so I applied that 3 times in 2014 (mid-May, early Sept, late October). I also applied some Dimension pre-em in late April 2014, although I don't think I needed it -- the only weeds I had to deal with were dandelions, probably because the neighbors yard was covered with them. I mulch-mow fairly high and leave the clippings. I rented a core aerator and did the entire lawn in Sept 14 (what a pain in the butt) because I hoped it would help with drainage -- the lawn seems to hold water like crazy, stays sopping/squishy wet for at least a day after any significant rain. It didn't really help with drainage, and unfortunately the lawn was too wet when I aerated especially in the backyard because there were a half dozen or so places where the aerator just tore huge gouges rather than pulling plugs. After aerating I overseeded with probably 5lbs of a sun/shade mix in the front/sides, and 5 lbs of Shade Select in the back (both from John Deere Landscapes). It doesn't seem to have helped or hurt the front or sides, but the back is probably in worse shape (certainly not better) this spring than it was last year.
So, what to do? I would really like to do something this spring about the moss and the very thin back and sides, as well as take care of at least the bare/dead spots in the front. I had been planning to topdress the entire lawn this spring along with overseeding, although I'm not sure what to topdress with -- screened topsoil, mushroom compost, regular compost? I can get mushroom compost for $28/yd just down the road (comes from the mushroom farms in SE PA), or just "regular" compost from a few places, varying from $20-$30/yd. If I overseed, I think I would seed first, then topdress making sure it was only 1/4-1/2" deep at most, mainly as a mulch to help retain moisture while the seed germinates, but also as an amendment for what I believe to be pretty crappy soil. Presumably I would want to rake/remove as much of the moss as possible prior to seeding/topdressing.
As I mentioned I'm also considering going organic, or at least semi-organic (until I use up the leftover chemical fertizer I have), and I wonder if using compost for the topdressing might be beneficial in getting some more microbes into the soil. I've seen the recommendation of 1 yd of compost/1000 sq ft of lawn, which puts me at 7 yd of compost. I would probably do only 5 yd for 7,000 sq ft, mainly because that's how much I can fit in the T-Tag dump truck I can borrow from a contractor friend to pick the stuff up and I'd rather not make two trips. Besides, spreading 5 yds of compost sounds like enough work, and I'd rather not do all 7 if I don't *need* to. By my math 1 yd/1000 sq ft comes out to just shy of 1/3 inch thick, so 5 yd would be about 1/4 inch, which should still be fine, yes? We have a TSC on the other side of town where I can get alfalfa pellets, and I'm sure I can find a feed store (we're in the middle of farm country) to get other organic fertilizer material as well. I also get plenty of leaves in the fall, especially in the backyard, and boy do I hate raking and hauling them to the curb for the township to collect -- I'd be happy to just mulch them up with the mower and leave them instead.
Finally, some photos (forgive the slight blurriness, my phone camera isn't great...):
Where my leaves sat for several weeks before the township finally came around last year:
W side yard: