Deciding whether or not to use fertilizer in your garden can be difficult. Do your plants need it? Can they do just as well without it? Before you apply a chemical fertilizer, try some compost. If your plants still seem sickly or are not performing as well as you would like, try a applying a quarter of the recommended dosage and see how your plants react. A soil analysis can also tell you the specific nutrients your soil is lacking. Most plants that are native to your area do not require fertilizer and are actually susceptible to disease and insect attack if fertilized. However, native plants will respond to a small application of nitrogen and phosphoorus immediately after planting to encourage root growth. Additionally, most members of the Leguminasae family are able to fix nitrogen from the soil themselves and do not require any additional fertilizer.

        The most important thing to remember is to fertilize when plants are actively growing, not when they are dormant.

        All fertilizers are labeled with three numbers which represent the percentages of nitrogen, phosphorus and potassium in the product. Therefore, a fertilizer with a rating of 10-5-5 is heavy on nitrogen, while one with 3-3-3 is equal in all three elements. Each element addresses a different aspect of plant growth.

• Nitrogen is essential for healthy growth, especially leaf growth.
• Phosphorus is necessary for healthy roots, flower and fruit production.
• Potassium is also necessary for healthy root systems as well as the plant's overall ability to resist disease.

        Fertilizers are either natural, synthetic or organic. Synthetic fertilizers are completely manmade. Natural fertilizers are made from naturally occuring minerals. Organic fertilizers are derived from living sources such as fish emulsion and bonemeal.