One of the biggest thing to know about maintaining soil, is keep it covered. (Except for a tiny bit where ground nesting critters can move in.) Weed fabric does NOT count as a cover. I loathe the stuff. It is useful under pathways and rock, but it has no place under mulch. I have seen normally beautiful “old” gardens soils literally turned to grey powder because weed fabric locked out moisture and nutrient cycling. I have used thick unbleached butcher paper as weed fabric when establishing a new space. It is thick, pretty darn durable, and breaks down as a high-carbon fungal food.
The second big thing to know about soil is leave it be. There is no reason to disturb soil (unless you are planting veggies- and that is debatable as well). Tilling and working the soil destroys fungal hyphae and knocks back the balance of fungal and bacterial biology. It also kills invertibrates like worms, ground beetle grubs and beneficial nematodes.
If your soil is poor and needs improving you can deep core aerate and top dress with mycorrhizae and high quality compost. This will get microorganisms down into the soil without turning the soil to powder first. You’d be surprised how quickly these organisms are moved through the soil profile by invertebrates and water. If you want to push the improvements even faster you can apply compost extract once a month to add to the soil biology but be sure you have compost, mulch or other food sources for the microorganisms.
When my family finds worms in impractical spaces we put them in a designated bed for the year. Each year we change the designated area so that worm populations improve throughout the property. It seems like a silly ritual, but its benefits are irrefutable.
Maintenance is a great way to close the nutrient cycle and provide healthy habitat for soil microorganisms. There is really no reason that any yard debris should ever leave your property. If you are up to it, you could even rent a chipper to take care of any fallen branches.
Chop and drop
Generally when I mention the term ‘chop and drop’, I get puzzled looks. It’s a perfect way to deal with the green waste produced on site. Once you prune an herbaceous plant, brush the surrounding mulch to the side, cut the debris into 2-3″ chunks, then cover over with the mulch that you brushed to the side. You can leave even larger chunks if you’d like; just know that it will take a bit longer to break down, and will be easier to see from far away. The smaller chunks visually blend in with the mulch a lot better.
A cool bonus to chop and drop is that it tells you how biologically active your soil is. After a few days peel your mulch back and see how your debris is doing. If it is breaking down quickly, you have healthy soil biology. If it is taking a long time, your soil may not be as biologically active as it could be. It might be a good time to do an application of compost extract.
Leaving or mowing leaves
Don’t forget about the great qualities of leaves. Instead of bagging and disposing of them, mow over them in your lawn area. If you go over them a couple of times they will turn into a powder that works its way down into your grass. (Most of their bulk is air, so they break down to nothing.) You could pile them on a bed as mulch, throw them into your compost as a great fungal food, or put them in composting bags where they will break down over the winter into a nice compost for spring. Load up the bags in fall, moisten them and forget about them.