The best magazine
The Benefits of Organic Fertilizer
When you want to add nitrogen to your soil you can take your pick of manure, (fresh or dried),homemade or commercial compost, sludge, and vegetable meals. Due to the high nitrogen content of blood meal and dried blood 12 to 15, these materials should be used more sparingly.
For phosphate you may choose from rock, bone meal, dried blood, vegetable meals, and manures. Potash sources are granite dust, wood ashes, kelp and many plant residues.
These materials can all be worked into the soil in spring or fall, they can be top dressed around growing plants, used as a mulch, or added to the compost pile. When you keep a high humus content in your soil many of these fertilizers will be more readily available. They will also stay available over several years. Organic fertilizers are available at feed mills, farm cooperatives, and local garden supply stores.
Natural mineral fertilizers are considered mainstays of organic gardening and farming. Natural rock fertilizers have been pretty much left out by the average gardener. The average gardener needs to take another look at natural rock fertilizers they furnish ample supplies of phosphorus and potash without which no plant can grow successfully. One thing to consider is the fact that natural mineral fertilizers put essential nutrients into the soil gradually over the years so the plants can absorb them as they need them, Because there is no shortages or abundance in the soil the plants stay in balance and as the nutrients are released the soil structure improves.
Source: ...