Hoagland solution
The Hoagland solution is a hydroponic nutrient solution that was developed by Hoagland and Arnon in 1938 and revised by Arnon in 1950 and is one of the most popular solution compositions for growing plants (in the scientific world at least). The Hoagland solution provides every nutrient necessary for plant growth and is appropriate for the growth of a large variety of plant species.
The solution described by Hoagland and Arnon in 1950 has been modified several times, mainly to add iron chelates, the original concentrations for each element are shown below.
The Hoagland solution has a lot of N and K so it is very well suited for the development of large plants like tomato and bell pepper. The solution is very good for the growth of plants with lower nutrient demands as well, such as lettuce and aquatic plants with the further dilution of the preparation to 1/4 or 1/5 of the original.
Procedure:
What many people may not know is that the Hoagland/Arnon nutrient solution formulations require one gallon of nutrient solution to be used per plant with replacement on a weekly basis. If any of these use parameters are changed, i.e., the volume of solution, number of plants, and/or frequency of replacement, plant performance will be significantly affected, this is a factor that may not be realized by people using the formulations.
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