Answer: Some people have a strong preference one way or the other between so called chemical vs. organic but both can provide nutrients to the plants. In my experience there may be occasions to use one over the other, for instance if there is an immediate severe shortage of nitrogen you may want to use a foliar feed to try to provide that as soon as possible. Sometimes it is more convenient to use the non-organic products. In the long run however I think regular use of organic mulch material as well as good quality compost will help build the soil and by encouraging healthy soil and soil organisms then you encourage healthy root growth. Do not overfertilize, it is actually better for the plants to be underfed than over fed. Many shrubs do not need fertilization to maintain healthy growth. Perennials seem to appreciate the extra boost in some cases but if you have a good soil management program they may not need it, either. To some extent plant performance will tell you whether there is a shortage of something, or not. Ideally you would run some soil tests and see what the soil is lacking and then fertilize based on the test results. Every fertilizer product whether it is organic or chemical will have an analysis on the label and this can be your guide as to how much to use. Also be sure to read and follow all of the label instructions so that you apply it correctly. Your local county extension should be able to help you with the testing and interpreting the results. In the meantime here is a link to site with more detailed information about soil and fertilizers.
I hope this answers your question.
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