Banana plants are heavy feeders and in order to grow healthy plants with large bunches plants must be well nourished. Regardless of whether or not you are experienced at recognising mineral deficiencies in the plants it makes sense to have a soil test which also includes the following micro-nutrients: boron, chlorine, copper, iron, manganese, molybdenum, sulphur and zinc. While required in far smaller amounts than the macronutrients they are still essential to good plant health and bunch formation.
It is possible to identify mineral deficiencies by the patterns of leaf discolouration and other markers on leaves which are deficient. For example, plants deficients in zinc will display a redness on the back side of new leaves that are in the process of unfurling. Without sufficient zinc leaf expansion and growth will be retarded, fruit length and diameter will suffer as will bunch stem elongation and bunch expansion. It can be difficult, if not impossible, to correct such deficiencies once flowering commences so ensure the plant is well nourished from the start and use foliar feeding to quickly correct deficiencies until the plant is able to access minerals from soil ammendments. Soil ammendments (fertiliser, compost etc.) need to be added to the soil but it will be quite some time until they are available to the plant.
Zinc Deficieny in a young plant
Posted: Thu 26 Aug 2021