Answer: I always assume my soil is poor and in need of amendments. This way I know that adding organic matter every year will help improve it. Plants thrive in well amended, well draining soils and won't grow well if soils are poor. Evergreen trees, or any newly planted tree for that matter, do not need to be fertilized when first planted. In fact, feeding a newly planted tree will force growth at the top of the plant when you really want it to spend time establishing a good root system. So, withhold feeding until the spring after you have installed a tree. Tree roots are deep so you can water in the morning or in the evening. I'd avoid noontime watering because of evaporation. If you build a watering basin or watering well beneath the tree by mounding up some soil along the perimeter, about 12-18 inches away from the trunk, you can fill the basin, allow it to drain, then fill it a second time. Do this once a week to keep the roots well hydrated. There could be a disease on the trees, or an insect infestation, or even winter damage. Check with your local cooperative extension office to see if they can offer explanations about the dying trees in Iowa. Good luck with your landscape.
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