ISHS Acta Horticulturae 145: Symposium on the Use of Fertilizers in Protected Vegetable Production
IONIC STABILITY OF THE ROOT ENVIRONMENT FOR INTENSIVE PRODUCTION OF VEGETABLE CROPS |
| Author: | C.M. Geraldson |
| Abstract:
The ionic stability of the root environments in hydroponic or soil culture has been evaluated with relevance to intensive production of vegetable crops. A 100 Mg ha-1 tomato crop grown in Florida's sandy soil requires 2 to 3 times the N and K per unit of time of that required by a 250 Mg ha-1 hydroponic crop. For most vegetable crops, as with tomatoes, stabilization of the root environment using the gradient-mulch concept has been associated with a potential for maximum production. Since converting to a full-bed mulch, average tomato yields in Florida have increased 100%. The system favors not only the preservation of all soluble nutrients, especially N and K, but provides all nutrients at a rate commensurate with requirement. Plant growth in both soil and hydroponic culture is strongly influenced by the ionic composition of the root environment. Precise definition of nutrient concentration and balance can be established by choice of nutrient components for the hydroponic culture. Maintaining that definition with regard to crop removal is more difficult. Precision definition of the root environment in the soil normally is impossible because of the dynamic nature of the components as well as the crop removal factor. However, with the advent of the gradient-mulch concept, it is possible to establish and maintain a stable root environment during the entire growing season. In this paper, the stability of the ionic composition of the hydroponic and soil solution will be compared and evaluated with regard to production. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
