Yes, you can make your own fertilizers. The ultimate avid gardener recipe would be the recipe to make super good, organic fertilizers for your own use.
For some people, home gardening is an expensive pursuit. But at one time people gardened because homegrown produce was far better and cheaper than anything from the store. Any of the farmers of years ago knew, just like we know today, that to have healthy plants, you need healthy soil. An interesting Web site for “down home gardening” is backwoodshome.com.