Monday, December 10, 2007
Plants are sometimes grown using a nutrient solution containing no N for the last 10 days. Many of the larger leaves yellow and wither as N migrates from old to new growth. The fertilizer should be complete, that is, it should contain all of the secondary and trace elements. Some fertilizers do not contain Mg. This is supplemented using Epsom salts, available at drug stores. Sometimes growers prefer to use more than one fertilizer. They find that changing the formulas and ingredients helps to prevent stresses and deficiencies. However, the chemicals in each fertilizer are blended to remain soluble (semillas de marihuana). Different fertilizer formulas may react with each other. As a result some of the chemicals may precipitate and become unavailable to the plants. To prevent this growers use only one fertilizer at each watering.