b'Deficiency symptomsA shortage of boron causes bad pollen in the flower or even the absence of pollen and fewer flowers, the petals of the flowers are smaller. The fruit therefore has a misshapen appearance. The root system is highly branched, theoverall plant growth may be less and growth points may die. The passive absorption of boron means that a lowsoil temperature in combination with a high RH (Relative Humidity) contribute to the deficiency, due to little or no evaporation the absorption comes to a standstill. Excess of boronAn excess of boron causes brown leaf tips and brown spotson the leaf. If the boron content is too high for a long time,the entire plant can die. Certain fertilizers can contain a high level of boron which can be phytotoxic.Excess of boronCopperCopper ensures that stems are lignified and is essential for various enzymes that make proteins, vitamins and sugars.A more intense odour and colour is also caused by copper. Copper is immobile and the defects are therefore first manifested in the youngest leaves.130'