Fertilizing and upcoming rain

I gave some of my young in ground fruit trees a shot of Miracle Grow soluble fertilizer, trying to give enough liquid so that it would penetrate the soil a bit. But with rain in the forecast 3-4 days away, I’m wondering if a steady rain might wash the fertilizer past the roots before it is taken up.

I’m wondering what the mechanics are of this type of fertilization. Does the liquid fertilizer bind to anything in the soil, thus keeping it stable until it’s taken up by the roots, or would a steady rain for several days just wash it further down out of reach of a young tree’s roots. And how quickly is it taken up by the roots when in soluble form?

Later…the predicted rain didn’t amount to much, this is S. Calif after all) and a week later some of the trees seem to be flushing noticeably. Would this be coincidence, or does soluble fertilizer work this quickly?

Different forms of water soluble nitrogen have different rates of uptake by roots and processing by the plant. These times range from six hours to one week in otherwise “good” soils. The secondary and micronutrients also have their own rates of up taking by the roots and processing by the plant. Hormones present in a water soluble are typically taken up within a few hours; e.g., dehydrated gibberellic acid. Note that plants will also retain some fertilizer components in the root zone for catalytic action and only uptake negligible amounts of those nutrients.

If you are concerned about a rainstorm flushing away recently added nutrients, consider the volume of water that would collect in your tree basin from one quarter inch of rain compared to the volume of water you used to supply the fertilizer.