Why on earth is dissolvable Miracle-Gro bright blue?
It stains hands, clothes and leaves a right mess everywhere!
A possible answer..
"Miracle-Gro and other soluble fertilizers are colored so that you can
tell that a solution is fertlizer water and not plain water. Many
growers use injection systems or proportioners that take up a
concentrated stock solution of fertilizer from a bucket or tank and
add it in a fixed proportion (so many parts per million) to an
automatic watering system. If the grower sees pale blue water coming
out of his irrigation tubing, he knows the system is working. Periodic
testing of the output ensures that the proportioner is callibrated
correctly. Likewise, a home gardener can see that the bluish stuff in
the jug is water with plant food and not drinking water or water for
the steam iron."
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