Marianne's Response

Osmocote Plus questions

I have started using Osmocote Plus in my garden for both in-the-ground plants and potted plants in an attempt to correct the yellowing of leaves. It does not seem to be working and I have a couple of questions: 1. Is there a way to tell if the spherical shells left on the dirt surface after several weeks are spent (empty) shells or if they are failing to release their contents? (They do not squish if I squeeze them). I realize that the directions say to work the pieces into the top couple of inches of soil. Unfortunately I am unable to do this because I have arthritis and the soil is very compacted (hard). I was hoping that when I water, the pieces would release some of their nutrients which would wash into the soil. Maybe this is not the case and the Osmocote pieces DO have to be surrounded by moist soil in order to release the nutrients?

2. If I have used too much Osmocote, can that make the leaves turn yellow?

Posted by Susan Revak on May 13, 2016

Marianne's Response

Good questions. First, the Osmocote does need to be moist and warm to release nutrients but the shell or coating releases the fertilizer very slowly over a period of months so you will not see instant results. The fastest fertilizer is a liquid such as Miracle Grow that you can use to water the foliage and the soil. Plants absorb nitrogen quickly through their leaves. 2. If you use too much Osmocote the leaves will not turn yellow - over fertilizing may present as brown tips on the edges of the leaves. Your Angel Trumpet plant is pretty tough - yellow leaves may be a sign that the roots are rotting from too much water so make sure the container plants have drainage holes and do not sit in saucers that hold the drainage water. Keep us posted on what happens, but I think you will see greener foliage in a few weeks. Keep growing, Marianne Binetti

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