Compost is the best soil conditioner you can use. The following statement from the Encyclopedia of Organic Gardening, published in 1973 by Rodale, is still true today (especially if you replace the word "typewriter" with "computer"): "The compost heap is to the organic gardener what the typewriter is to the writer, the shovel is to the laborer and what the truck is to the driver…It is the tool to get the job done. In the case of the organic gardener the job is the creation of the finest garden soil he knows how to create, and compost has proven itself through thousands of years of use to be the best tool for the job."
I experienced the benefits of using compost when we installed an edible garden at my daughter's elementary school. We worked with a local company that provided the soil, a mix they developed using green waste from the produce department at a major organic grocery store chain, along with byproducts from pine forests, cotton gins, peanuts, chicken litter, granite dust and "biodynamic soil preparations." The result was a soil that is rich in beneficial micro-organisms. Our harvest was amazing; our vegetables were not only beautiful but they tasted delicious. Even our school principal (who is not a gardener) was amazed and is thinking about adding some raised beds to grow vegetables at his home.
In your home compost pile you can add dead leaves, grass clippings (not recommended if you use chemicals on your lawn), and kitchen waste including egg shells, produce, coffee grounds (but no meat or animal fats). There are many different methods for composting, all with the same goal of creating dark humus rich in nutrients that you can add to your soil.
Add compost to your garden in the fall or spring. If it is broken down at least half way (still fibrous) you can apply it in October or November and it will be decomposed by spring when you plant. There are different recommendations for the amount of compost to use, but at least 1 to 3 inches per year should be mixed into the soil. You can take a soil sample to evaluate your soil fertility. Most counties will test your soil sample for a small fee through the local extension service.
While your plants can't distinguish where they get their nutrients (the three main ones are nitrogen, phosphorous and potassium or N-P-K) from Organic or synthetic fertilizers, by using compost you won't have to worry about burning roots, and you will be adding many beneficial micro-nutrients. You can look forward to growing healthy, productive plants.