Three experiments were conducted on a Vertisol of the southwest region of Puerto Rico to evaluate the effects of no-till vs. three different tillage techniques on the yield of corn, pepper, watermelon, eggplant, bean and tomato. Soil treatments consisted of no till (undisturbed), minimum till (chisel plowing), deep till (disk plowing to 45-cm) and conventional till (15-cm depth). Each treated plot was split into two or three subplots where test crops were planted. A positive response to conventional till was observed for pepper, watermelon, bean and tomato. No statistically significant differences were observed when the yields of all crops grown on minimum-till plots were compared with the no-till treatment. This suggests the possibility that corn and eggplant can be planted in no-till soils similar to Santa Isabel clay without reducing yield at least for 1 year. Bean, tomato, watermelon and pepper, however, might require some type of tillage. Nevertheless, the results in general substantiate the view that production costs can be lowered by decreasing tillage input without reducing yield.