Mixing NPK fertilizers with micronutrients is an effective way to ensure your plants receive all the nutrients they need for healthy growth. While NPK fertilizers contain macronutrients that are required in high quantities, micronutrients such as iron, boron and zinc contribute to plant health at much lower concentrations. Adding micronutrients to your fertilizer regime can help increase yields and improve the overall quality of your crops. For example, adding iron to a fertilizer application may help treat chlorosis, a condition where leaves turn yellow or green due to a lack of adequate iron uptake by the plant. Additionally, adding zinc may help prevent bud abortion and inhibit fruit cracking in tomatoes. There are several ways to mix NPK and micronutrients, depending on the products you are using. For dry fertilizers, simply mix together the desired amount of each fertilizer in a bucket or spreader. For liquid fertilizers, you can either mix together different products in a tank or apply them sequentially through an irrigation system. No matter which method you choose, be sure to follow the application rates recommended by the fertilizer manufacturer to avoid overloading your plants with nutrients. Excess nutrients can lead to leaf burn, root damage and other problems. Also, be aware that some micronutrients can interact with each other and should not be mixed together unless specified by the manufacturer.