Page "Hydroponics" Paragraph 6

Two other plant nutritionists at the University of California were asked to research Gericke's claims.

Dennis R. Hoagland and Daniel I. Arnon wrote a classic 1938 agricultural bulletin, The Water Culture Method for Growing Plants Without Soil, debunking the exaggerated claims made about hydroponics.

Hoagland and Arnon found that hydroponic crop yields were no better than crop yields with good-quality soils.

Crop yields were ultimately limited by factors other than mineral nutrients, especially light.

This research, however, overlooked the fact that hydroponics has other advantages including the fact that the roots of the plant have constant access to oxygen and that the plants have access to as much or as little water as they need.

This is important as one of the most common errors when growing is over-and under-watering ; and hydroponics prevents this from occurring as large amounts of water can be made available to the plant and any water not used, drained away, recirculated, or actively aerated, eliminating anoxic conditions, which drown root systems in soil.

In soil, a grower needs to be very experienced to know exactly how much water to feed the plant.

Too much and the plant will not be able to access oxygen ; too little and the plant will lose the ability to transport nutrients, which are typically moved into the roots while in solution.

These two researchers developed several formulas for mineral nutrient solutions, known as Hoagland solution.

Modified Hoagland solutions are still used today.