There's a difference between mowing grass tall and letting it go completely. One of the side effects of mowing is to encourage rhizomes and tillers, so the grass tends to fill in better. If there are already weeds in the lawn, simply growing the grass tall won't get rid of them. You need to get rid of existing weeds, because the tall mowing only helps keep other weeds from sprouting. There are really several things involved, sometimes called cultural practices. One is to mow tall. Another is to mow no more than 1/3 of the height of the grass. Another is to water deeply but infrequently. The 1/3 rule doesn't directly discourage weeds, but it helps keep the grass healthy. watering infrequently makes it difficult for the weeds to germinate (they need to stay moist for a while to germinate). If they somehow stay moist long enough to germinate (regular rainfall, for example), the tall grass will block sunlight so the weeds that do germinate don't survive.

Remember what wants to be here is trees. Lots and lots of really big trees. With very few exceptions, any where left untended for a while is going to turn back into jungle. By far the easiest, most efficient way of beating back that jungle is by lawnmower. The other choices are herbicide, which I assume is a non-starter, and hand weeding, which takes a lot more time. So the further you get away from a mowed lawn, the more difficult the maintenance becomes. This is an enormous reason that lawns are so ubiquitous. They are easy. It does sound like there are places grass is going to be difficult because of the shade. Those places are going to be tricky because shade groundcovers aren't good for playing on. Either they can't stand the traffic, they trip people with vines, or both. Bark mulch might be a good solution for now, though it will have to either be weeded occasionally, or mowed. Weeds are less exuberant in shade, so hand weeding isn't as taxing as it can be in a sun bed. In the sun, overseeding with white Dutch clover won't hurt, but you will still be doing normal mowing. There really isn't a good way around that. One thing I have noticed, is that people who do not want to be identified with Lawn Warriors tend to significantly underpower their mowers, making lawnmowing a harder and more time consuming job than it needs to be.

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.

When we bought this property back in 1999, the soil was heavy clay (I swear we could have made pots with it!) I had recently become disabled so heavy digging - or even adding compost or most other such soil amendments was not a very viable option. Yet I wanted a garden.... Around that time MYKE brand mycorrhizal fungus supplement became available so I used the appropriate type of that whenever I planted anything, planted densely (no bare ground!) and then left as much dead plant material (e.g. fallen tree leaves and pine needles, prior year’s leafy perennial foliage) on the ground to ‘compost in place’. I haven’t used MYKE in years now - it got harder to find, and I figured my previous years of use of it should have boosted the population levels of mycorrhizal fungus in the soil, making the supplement less necessary. Most of the soil here is now pretty decent! Digging rarely encounters nasty red clay any more. I still leave as much organic matter (leaves etc.) as possible on the soil and plant very densely. It works for me.... My advice is to read widely about all things garden, and experiment with what makes sense to you. Then continue to do the things that work well for you in your garden. I think one of the biggest ‘myths’ is that you need to be born with a ‘green thumb’. You just need to have the interest and persistence to figure out what works for you.