Role of mulching in weed control of organic tomato

During our examinations we compared weed control effect and yield increasing effect of 8 different types of mulch in tomato. Untreated, hoed and herbicide treated plots were used as control. Years of the experiment were 2000-2005, years with different weather conditions. In tomato according to summarised results of the years 2000-2005 black plastic covering, paper, and grass clippings were good in suppressing weeds. Examining yield in 2000. plots with black plastic and paper coverings and in 2001 the ones with black plastic and grass clippings gave higher yield than uncovered herbicide treated control treatment. In the extreme year 2002 there was no significant (SD5 %) difference among the treatments for the yield. 2003 was a quite and year and tomato gave uniformly low yield in every plot. In 2004 yields from plots covered with black plastic foil, paper, straw and legume clippings were significantly higher than in herbicide treated plots. In 2005 necessity of mulching was proven because yields of the covered treatments were significantly higher than the one of the herbicide treated control treatment.