Bareroot nurseries apply the mineral nutrients that are needed for rapid growth with chemical fertilizers. Unless soil tests show other nutrient deficiencies, nitrogen and potassium are the only fertilizers that are typically applied - remember that phosphorus is typically applied before sowing. During the growing season applications are called "top dressings" because they are done over the top of the crop. The application rates are determined by experience or from chemical tests of the soil and seedling foliage.
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