Green bean fertigation must be controlled carefully since they are extremely fast growing. There are pro’s and con’s of fast growing crops. An advantage can be that any deficiency or toxicity can be outgrown quickly. The disadvantage is that the crop can develop one of these physiological disorders very quickly. The speed at which green beans react to low nitrogen is amazing, equally, it is rectified within days. Green bean fertigation needs attention and control every day of the week. Since the plants are very soft they tend to react very quickly to any form of stress. Beans are extremely susceptible to water stress situations such as water-logging and drought (This includes too high EC levels). When growing beans it is recommended to use a finer textured growth medium in order to reduce the number of irrigation cycles per day and to create a comfortable environment for the roots to develop. Add one short cycle at the end of the day to ensure that plants do not stress due to lack of water. Bean tissue is very succulent and is very sensitive to water stress. If it is allowed to stay under stress for a couple of days, a significant decrease in yields will result.
Very little information is available as to the correct grean bean fertigation schedule. Experience has shown that grean beans can successfully be grown with a tomato crop Type of intercropping, or sharing the green bean fertigation program with a tomato crop in the same greenhouse). Thus any formulation that will work with tomatoes should apply to beans.