How to Feed Your Soil
As plants grow, they consume nutrients in the soil that must be replaced. Over time, soil becomes compacted, even if it's not being walked on, and it needs to be loosened. And perhaps most importantly, all the living organisms in the soil need a change, a boost in their environment. All those things can be achieved by the routine addition of various soil amendments. Not fertilizers, per se, but different types of organic matter, which may not contain much in the way of nutrients but instead will enhance the structure of the soil.
Without a doubt, the best soil amendment in the world is compost. But not everyone maintains a compost pile or bin (too much work, not enough space, whatever).
So then what? There are a number of bagged products that represent the next best thing to homemade compost.
This bag of composted cotton burrs is a byproduct of the cotton industry that might have otherwise wound up in the trash stream. Another mixture is a blend of cow manure and alfalfa, both byproducts of the dairy industry.
Some other good options are pure cow manure, topsoil and mushroom compost. Each of these can be used separately to amend the soil, but try mixing them to get the best that each has to offer.
If you are going to create a mix, consider adding a little helping of two things: One is greensand, a product-minded form of the ancient sea beds and which contains a fair amount of potassium and dozens of trace elements. The other is bonemeal, which is high in phosphorous and calcium. Neither will rapidly stimulate plant growth, but they are essential for growth and they stimulate microbial activity.
How to Feed the Soil
Once you've got your mix down, it's time to add it to the soil. There are a number of ways to do it.
Option No. 1: The simplest way involves tossing one to three inches of the stuff on top of the existing soil and letting nature do the rest. In time, organic matter will break down with the help of earthworms and various small microbes.
Option No. 2: You can also gently work the organic matter into the soil by turning the top six inches or so. This process isn't entirely necessary, but if you have drainage issues related to sandy or heavy clay soil, it will remedy those problems faster.
Option No. 3: If you intend to amend an already mulched bed, you'll first need to pull the mulch back, and then apply the soil amendment, and finally put the mulch back.
Option No. 4: If you don't want to go to all the trouble of Option No. 3, or if you're short on soil amendments, you can simply apply the stuff around the perimeter of established plants. Think before you work it into the soil, though, because you could damage plant roots.
You can add soil amendments to the lawn as well, though you may want to sift it first so you can apply it with a spreader.
Around established trees, you can use a bulb auger to drill several 6-inch holes in the ground and fill those with soil amendment.
No soil amendment? Blow all your fallen leaves back into your beds, where they'll slowly decompose into one of the best soil amendments of all.