FOLIAR FEEDING
A quality synthetic fertilizer does not harm a plant when
used correctly. It adds nutrients that are immediately available for plant uptake and does not contain toxins. Synthetic
fertilizers do not, however, feed the soil and so by themselves
cannot make the most complete nutrient regimen and provide optimal growth and maximum yield.
How Does Foliar Feeding Work?
Though many researchers report that nutrition can be
absorbed directly by the stomata in the leaves, many
experts claim this is not what happens as once the nutrients
enter through the stomata, the channels are lined with a
waxy substance that prevents absorption. These reports say
that there are trillions of tiny transcuticular pores on the
leaf surface that are readily permeable to solutions with
correspondingly small molecule sizes. The miniscule sizes
of these pores limits what type of nutrients can actually be
absorbed. These debates can be further researched using
the QR code at the end of the article.
If, however, some of the nutrient solution that is taken into
the stom ata can actually be absorbed and utilized, in addition to the access through the transcuticular pores, this, too,
should be considered. The debate over this aspect of foliar
feeding does not appear to be over.
Stomata are usually located on the underside of leaves and
act primarily to allow transfer of oxygen and water out of
the plant (transpiration) and carbon dioxide into the plant.
They are small openings but they are larger than transcuticular pores, so they allow larger molecules to enter, including
liquids and various chelated minerals. It is a secondary function that the stomata provide a point of useful absorption for
nutrients—secondary but very beneficial.
“It may seem as though the
goal of organic soil feeding
might be by-passed by
practicing foliar fertilization.”
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Maximum Yield USA | June 2016