AgTech: Plant Nutrition

Soil PH is the best starting point for plant growth. Each species will have a desirable PH level for the soil or growing medium. Most fall into a bell curve somewhere in the middle. PH as you probably know is the measurement of the acidity or basicity. Sulfur can be amended to soil to lower PH and lime can be added to increase PH.


Potassium Sulfate - Quickly provides potassium to leaves. Can be mixed into soil or water. Best to alternate days to avoid salt build up in roots. Will turn leaves green when PH and cal-mag are in range. Potassium is used at about 6 times as much as any other element listed.

Calcium Sulfate (Gypsum) - The cal part of cal-mag that is a micro nutrient providing calcium without altering PH levels. Important for strong branch formation. Best to mix with soil as it is not water soluble.

Magnesium Sulfate (Epson Salt) - The mag part of cal-mag provides magnesium to plants. It helps make plants green and bushy.

Urea - Used to supplement nitrogen in small quantities roughly once a week. Nitrogen in plants supports plant growth when the PH is with in range. If the oldest leaves are dying off, this is likely a nitrogen deficiency. Nitrogen is the strongest and should be used the most sparingly.

Phosphorous - Helps plants produce ATP the cell energy molecule. Important for plant vigor during all growth stages. Plant stems will change to a red, purple, or blue when there is a phosphorous deficiency.


The above 5 elements make it possible to recycle soil for years and maybe continuously. Leaf biomass can be amended to soils to increase long-term nitrogen capacity. Excess nutrients will cause nutrient burn. Occasionally excess nutrients or salts build up, flushing roots with water until the runoff is clear fixes root build up. Excess root water can be fixed by adding more air flow to leaves.


Note that, calcium nitrate may be a better source of nitrogen and can replace calcium sulfate to simplify the mixture. More testing is needed. If you have any suggestions please send them.

Published — 9/27/2021 | Updated — 12/2/2021 | Views — 52 | Rating — 75% Liked | Votes — 4

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