Patent ID: 8721759

Claim:
A method of prolonged-termed continuous fertigation of an agricultural field during a crop cycle, said agricultural field being irrigated by means of an active irrigation system having flowing irrigation water upstream of said agricultural field, said method comprising the steps of: (step 1) continuously charging a nitrogen-nutrient feedstock comprised of a first nitrogen-nutrient-feedstock raw material to said active agricultural irrigation system by sub-step 1a of: (sub-step 1a) continuously charging said nitrogen-nutrient feedstock to a stream of said flowing irrigation water upstream of said agricultural field, wherein said nitrogen-nutrient-feedstock raw material is selected from the group consisting of fast-release-nitrogen-source nitric acid, slow-release-nitrogen-source urea, fast-release-nitrogen-source calcium nitrate, fast-release-nitrogen-source magnesium nitrate and slow-release-nitrogen-source ammonium hydroxide, wherein said stream of flowing irrigation water has sufficient flow to intermix said nitrogen-nutrient feedstock with said irrigation water, generating a dissolution exotherm, wherein said nitrogen-nutrient feedstock is charged at levels within the system solubility limits and wherein said stream of flowing irrigation water has sufficient flow to dampen said dissolution exotherm, whereby said irrigation water is converted to treated irrigation water; (step 2) irrigating said agricultural field with said treated irrigation water; (step 3) repeating step 1 and step 2 each irrigation day over a prolonged term; and (step 4) changing the nitrogen-nutrient feedstock by changing the balance between slow-release-nitrogen-source raw material and fast-release-nitrogen-source raw material during said prolonged term.