Calcium and Boron have a close relationship in the plant. Their absolute concentrations and the relative ratio between the two affects how much of each can be absorbed. Both play an important role in growth points, or rather meristematic tissue. Although both these nutrients are not problematic in most crops, it is good to know [...]
The ammonium/nitrate ratio in the nutrient solution is important since it can have a significant effect on the quality and total yields of the tomato crop. Both NO3- and NH4+ are the most important sources of nitrogen in the plant. The ammonium/nitrate ratio has only become critical, and a problem, since growing without soil became commercially [...]
It is often quite difficult to identify a deficiency or toxicity symptom in the field because they never really occur as a single element deficiency or toxicity. Each of the elements are inter dependent and they influence each other within certain ratio’s. One would find for instance that phosphorus toxicity, is expressed as either a [...]
First it is important to understand which nutrients are included in the various fertilizers and in what amounts. It is important to distinguish between macro and micro elements. The macro elements are taken up in large quantities and the micro elements in smaller quantities. Although the micro elements are taken up by smaller amounts, it [...]
NITROGEN Toxicity Symptoms Plants are dark green in colour with excessive amount of foliage Root growth is restricted Reduced flowering and seed production Plants wilt quickly under water stress situations Susceptible to diseases. Deficiency Symptoms Plants are light green in colour starting at the bottom leaves Restricted growth Leaves are smaller than normal Purple discolouration [...]
Sulphur (or sulfur)is also known as the “ignored primary nutrient” since not many people realize that it is one of the macro nutrients and is extremely important. The role of S has been ignored for long times since its effect on plant growth was not known. Researchers inadvertently applied large amounts sulphur through the use [...]
Magnesium was discovered by Nehemiah Grew in 1695 by evaporating mineral waters in Epsom England. It was only in 1808 that Sir Humphrey Davy isolated the metal and identified it as magnesia oxide and termed it magnium. The metallic magnesium was first isolated by A. Bussy in 1828 and in 1883 the first metallic magnesium [...]
On average, more growers have calcium (Ca) related problems than any other nutrient. These problems occur in areas of low humidity and high temperatures. Calcium forms part of cell walls and any deficiency is marked by the breakdown of cell tissue leading to some form of internal “browning”. The average concentration in the plant varies [...]
Potassium is the most abundant monovalent cation in plant tissue. It is highly mobile which explains why deficiency symptoms can occur so rapidly. The concentration of potassium is directly related to the physiological activity of the plant. That is why young plants have higher potassium levels than older mature plants. Potassium is essential in regulating [...]
