Thanks, David!! And yes, it used to be a mess. But I don't subscribe to a "this vs that" method of trying to attribute success (or failure) to a single component. I've come to realize that the more I study things, the more the interrelationships are the critical items. In other words, it's not "soil chemistry vs soil biology", but how the two of them interact and support each other. A good soil chemistry allows a great biology to grow, which acts as a reservoir for food for the lawn. This avoids the "yo-yo effect" that we see in the regular long-term use of synthetics. A good chemistry provides lots of nutrients in good ratios to each other and massive growth. To answer your question about what I did, I concentrated on getting Phosphorus, Potassium, Calcium, Magnesium, Sulfur and the micronutrients (Iron, Zinc, Manganese, Copper and Boron) settled in the right proportions to each other. Notice that I ignored Nitrogen and pH. Once the other items are settled properly, the pH will find the "sweet spot" all by itself, and anything organic supplied will supply Nitrogen into "the bank". It's not a recipe for making the lawn (or garden) look great next week, but the soil will almost manage itself if you get the chemistry and biology working together. At this point, I can feed it some Milorganite or Soy Bean Meal and it will handle the rest all by itself. Then I spend my time trying to help others that want to do the same, or chasing the deer out of my Hosta.

I agree it's a lot of shade for Bermuda, but could there be something else going on here? Were both of the pictures you posted on 4/24 taken at the same time? If you look at those pictures, the grass under the trees is really sparse - even outside the canopy. Obviously the shadow will move throughout the day, but the trees didn't even have leaves on them in that picture. On the other hand, the grass from the "other side of the driveway" where "it gets full sun and no erosion" looks good for mid-late spring. For what it's worth, I have several trees in my yard and the Bermuda is typically a little thinner there than other areas of the yard, but in some cases its actually a little thicker. In fact the areas were I seem to get the best performance seem to receive at least some shade during the day by a nearby tree. All of these areas are relatively flat though. I do have an area on the east side of the house that really struggles. The lawn only receives sun from about 10:00 am until 3:30 pm. It is bordered on one side by my neighbors trees, and on the west by my house. In addition, there is a fairly considerable slope and which has resulted in some erosion.

This is a nice initial soil test. There's some work to be done, but the starting point on this soil is pretty good. EC 6.2: Sandy soil, with a little silt. Plan on testing this soil yearly as it'll shift fast. OM 2.1%: At the lower border of Fair, starting to trend toward Poor. With your lower EC, I'd always feed organically, always mulch mow, mow in all your fall leaves, steal your neighbors' leaves in fall, and so on. While not an emergency or anything, bringing this up will positively impact your lawn quality, raise your EC a little bit, and vastly improve water retention in your soil. pH 7.0: A little high due to excess magnesium in the soil. Sulfur 13: Normal, with tons of margin to play with if I need it. I'll use a little of the margin, but not very much as your soil won't require that much playing. Phosphorus 101: Low but not extreme, this is still negatively impacting your lawn quality. Target in this case will be around 220. I recommended starter fertilizer below. Just choose the cheapest as they'll all target around 1 pound of phosphorus per thousand square feet. Calcium 65.7%: Exactly optimal. The soil shows a tiny deficit of 48 pounds per acre (about 1 pound per thousand) but we can ignore it this year. That's too small to bother with and difficult to correct without going over the top. Given your pH, we definitely don't want to do that. Magnesium 25.0%: Very high, which will tend to give you a tight, impenetrable soil. Avoid all magnesium sources, including dolomitic limestone and Epsom salt. Let's give this a year to leach out normally, by which time you'll probably need calcium anyway--and we can use one step to add a little Ca while abolishing a touch of Mg at that point if needed. Potassium 2.2%: Although OK by the percentage, the numbers are low. Plus I'm a fan of moving K to the upper part of the recommended percentages or even a little beyond. It improves heat and cold resistance, disease resistance, and insect resistance. Most landscape and garden stores will order potassium sulfate (sulfate of potash) for you, or you can get it online. Recommendations below. Minor Elements: Boron is low and I discuss that next. Except for iron, all others are OK. Iron is below boron. Boron 0.38: Low. Boron is used in photosynthesis and cell differentiation, so it's kind of important. We use 20 Mule Team Borax as the boron source, which is available at your local grocery store in the laundry section, plus Milorganite as a carrier. In a wheelbarrow or the like, dump the Milo. Spraying very, very lightly with water (I use a spray bottle like the kind people use to damp their clothes when they iron) will help the boron stick. Add the recommended amount of 20 Mule Team Borax and stir, spraying occasionally to get the stuff to stick to the Milo. Then apply over the recommended area. So if going for bag rate Milorganite (1 bag per 2,500 square feet), you'd add 10 tablespoons of 20 Mule Team Borax. Iron 77: Low. Not deficient, but not going to give you the best color or best photosynthesis in the lawn. Any time you like, apply Milorganite to slowly raise the iron levels in the soil and organic matter levels in the lawn. The boron listed above only goes once, on July 1. The rest of the Milo applications should be with nothing added. Recommendations: Memorial Day Weekend: Apply starter fertilizer at bag rate. June 15: Apply 2 pounds per thousand square feet of potassium sulfate. July 1: Apply 4 tablespoons of 20 Mule Team Borax in Milorganite. Labor Day: Apply starter fertilizer at bag rate. September 15: Apply 2 pounds per thousand square feet of potassium sulfate. October 1: Apply starter fertilizer at bag rate.

Search for 'surfactant golf course' in the journals. Every land grant university in the country has been doing those for decades. The reason golf courses need all the tools is because they absolutely have to have green grass every day of the year. They force feed and force water it. What happens is they develop a hydrophobic fungus growing on the surface of the grass and soil. When that happens they can water all day long and it just sits on top and evaporates. This is what I get from reading the journals I alluded to above. That sitting water promotes the hydrophobic fungus. In an attempt to break through that surface they tried spine aeration. The spines poke through the surface layer of fungus and allow moisture to penetrate. That works to the extent that the spines have a certain spacing. So the water enters the soil separated by the spine to spine distance. Another attempt to solve the hydrophobicity problem was to use a surfactant like Cascade Plus. That product seems to work in every study. The surfactant has the distinct advantage of breaking through the fungus everywhere so spine to spine distance means nothing. The surfactant has a side effect of softening the soil. We use it simply for the side effect. But if you would rather break your back bouncing around behind a $250, 500 pound, rental core aerator instead of spending 30 cents and getting a little wet, you go ahead. I'm not coming through the screen to grab you by the throat. I would hesitate to recommend to others anything outside of personal experience or studies from reputable Universities or professional organizations like the USGA or field turf organizations. That's great for you. We're not hamstrung by that self imposed restriction. Although I did believe the shampoo method of soil softening was bunk until I tried it. Now look at me shouting about it. I also advocate mowing most grasses at "the highest setting," rather than the university recommendation of mowing Midnight Kentucky Bluegrass at 2.65498256 inches and Chocolate Kentucky Blue at 2.65829683 inches. The point is not to mow it at 1 inch. It needs to be tall so just friggin' keep it simple for the homeowner who doesn't have a $5,000 lawn mower to adjust it to fractional inches. I also advocate watering deeply and infrequently. My land grant university in California taught us to water daily. But here in these forums there was a discussion (kind of a rugged discussion) about the benefits of watering daily versus deep and infrequent. I lost that one. The winner was a lawn care professional from Phoenix who convinced me that if he could water his clients' lawns once a week, that I should be able to do the same. Well whaddaya know, I tried it and he was right. It might be interesting to know that there is no university research to prove that plowing the ground has any benefits to farmers. People have been doing it for 10,000 years with no research. But there are those no-plow converts who swear up and down that they get better results than when they were plowing. Do you need the science when your pappy tells you it's true? Sometimes you do. Why not core aerate? Because the cores bring old weed seeds to the surface and sunlight giving them a new chance to germinate. Because removing the cores destroys the soil structure adjacent to the holes as that soil must melt away to fill the holes. Similarly the cores on the surface melt coating the surface with un structured soil. Because the soil microbes at 3 inches deep, now exposed directly to the air, will be destroyed simply because they bury themselves to get away from the air. Because if you're removing cores containing rye or fescue plants, those will not regrow to fill in where you removed them. For me the number 1 reason not to core aerate is because Mother Nature does not core aerate. If it was an important thing to do She would have created some creature somewhere that had hooves hardened in just the right shape to penetrate the soil and remove cores.