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Nutrient Deficiencies
Hydroponics Lab #1 Activity
(continued)
Nutrient Deficiency Index
*The deficiencies in this lab are either of the following:
Nitrogen is the most important nutrient for healthy plants. Farmers should become experts at spotting nitrogen deficiencies.
As a mobile nutrient, nitrogen deficiencies start in old growth and move to new growth. A typical symptom is total chlorosis
(yellowing) starting from the beginning of the old leaves moving up the plant toward new growth and stunted growth.
Phosphorus is another common mobile nutrient deficiency. The symptoms are much more subtle and slow than nitrogen. The
most common early symptoms are stunted growth and lack of health. Advanced phosphorus deficiency leads to the leaves of the
plant turning darker, or gaining shades of red/purple. Note: some plants are supposed to have darker or purple shades—know
your varietal!
Magnesium is a common mobile deficiency in hydroponic systems. Magnesium deficiency can easily be mistaken for nitrogen
deficiency, due to similar symptoms. The most recognizable feature of magnesium deficiency is that the chlorosis acts in a
different way than that of nitrogen deficiency—where the chlorosis caused by lack of nitrogen creates total-leaf chlorosis,
magnesium deficiency creates interveinal chlorosis. Interveinal chlorosis is when the veins of the plant leaves retain their color,
but the leaf tissue loses its color.
