SOIL SALT ACCUMULATION IN THE GREENHOUSE. WHAT TO BE DONE.

Soil salt accumulation, airborne diseases and greenhouse pest are the common problems faced by greenhouse farmers. Today, I want us to look at soil salt accumulation.

Greenhouse soils are held in continuous production for a long time under conditions of heavy leaching. As a result, micro nutrient deficiencies are a common problem and most farmers mistake them for pest effects or diseases on crops. Under these conditions plants will exhibit nutrient deficiency and toxicity symptoms. Accumulated salt levels will hinder absorption of micro nutrients by plants. 

Salt accumulation in soil is occurs when there is accumulate fertilizer and fertilizer residues, stagnant water in the soil in the absence of leaching, precipitation or plant uptake, cropping system (no rotation plan), irrigating with water with modest amount of salt and application of sprinkler and /or flood irrigation in hot arid climate.

Soil testing, which involves PH and soluble salt level analysis, is the sure way of ascertaining the levels of micro nutrient deficiency and toxicity levels in soil to warrant appropriate action. it is essential that every greenhouse farmer has a PH meter to analyze soil PH regularly and an EC meter to test the soluble salt levels. More accurate and elaborate analysis can be done in commercial institution laboratory available in the country. However, the most simple and quick way to evaluate soil nutritional status is by visual diagnosis. When observing a disorder, the plant parts affected must be noted as well as their respective ages. are the symptoms on the stem, fruit, flower or growing points of the plant? What is the nature of the ailment? Is the tissue chlorotic (yellow), necrotic (brown) or deformed? With the right description of the color pattern and location of the disorder (necrosis, chlorosis or deformation), You can find assistance from a qualified crop specialist.

Foliar(leaf) analysis is another very effective method of assessing the nutrient status of plants. Leaves are sampled and collected at a particular stage of crop development. Because nutrient content on a plant varies with leaf position, collect similar plant parts from sampled plants in you crop field/greenhouse for comparison against a standard.Routinely, samples need to be taken every four to six weeks otherwise immediately in case of suspected growth problem. Samples taken should have been grow under similar conditions ie root media, fertigation and husbandry.Some plants are very sensitive on slight fluctuation in soil nutrition. You need to grow such crops amongst the other high value crops. some of the best indicator crops are; lettuce, cucumber and tomato.

Fertilizer application and soil PH regulation are the treatment to these plant disorders.

To manage salt accumulation in the soil, encourage leaching of excess salts and remaining with only the required amounts in soil, drain excess salts, improve on fertilizer management, do soil amendment (correction) and water treatment.