I’m not going to even pretend that I know a whole lot about the use of organic soil amendments in gardening, but here’s what I do know: Organic soil amendments take the place of common synthetic fertilizers — Americans spend an estimated $5 billion a year on the chem-leaking stuff — in adding beneficial nutrients and minerals into soil, preventing erosion, and helping soil retain water. The end result? A naturally healthy garden free of fossil fuel-based-chems.

Organic soil amendments come in all shapes and sizes — compost, animal manure, plant-based manure, mulch, lime and animal waste products like blood meal and fish meal — and often serve specific purposes.

Since I don’t know my acidic from my alkaline nor do I have the NPK (nitrogen, phosphorus, potassium) nutrient ratio committed to heart, below are some helpful resources and a video from dreadlocked gardening authority Tracy DiSabato-Aust to fill you in on the specifics (“not all poo is created equal”) before you go sprinkling bat guano on your garden.

GreenYour.com — “Use organic soil amendments:” This easy-to-follow, 1-2-3 guide covers the various organic soil amendments and their benefits. Written by Massachusetts-based, greenthumbed guru Lynn Jones.

The Dirt Doctor — “Acceptable Organic Soil Amendments and Fertilizers:” The dirt on what types of soil amendments are free of potentially toxic chemicals and safe to use in garden, as recommended by the Texas Organic Research Center.

Vegetable Gardening Guru — “Producing Garden Vegetables with Organic Soil Amendments:” A comprehensive look at how to use organic soil amendments from the University of Florida Cooperative Extension.

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.

The first amendments
The 411 on gardening with organic soil amendments like compost, manure and natural fertilizers.