Abstract
Guava is an important fruit species but poorly studied for the effect of humic substances and soil mulching on its nutrition and fruit production. Thus, an experiment was conducted to evaluate the nutritional status and fruit production of guava as a function of humic substances and soil mulching in Brazilian semiarid. The experimental design was in randomized blocks with treatments distributed in a factorial arrangement (5 × 2) referring to humic substances doses (0, 10, 20, 30 and 40 mL of Humitec plant−1) and organic mulching (with and without organic mulching). Nutritional status of guava is affected by humic substances and soil mulching. The use of humic substances combined with soil mulching promotes optimum supplies of nitrogen, phosphorus, calcium, sulfur, boron and iron, but not calcium, copper and zinc. Under sandy soil and semiarid climate it is possible to recommend 40 mL L−1 of humic substances and soil mulching.