1. A motorized hand-operated cultivator comprising a carriage adapted for movement over ground to be cultivated, a handle attached to the forward end of said carriage for drawing the same toward the operator, a vertically reciprocatory member pivotally secured to said carriage, motor means mounted on said carriage, cam means driven by said motor means and in driving engagement with said member to vertically reciprocate the same about said pivot, a set of horizontally spaced and pointed tines secured to said reciprocatory member for vertical reciprocation therewith and extending rearwardly from the opposite end of said carriage, said tines continuing their extension in a downward reverse curvature such that they terminate pointing downwardly and forward at a level lower than said carriage with a horizontal spacing between tines which is sufficiently small to properly break-up the soil yet sufficiently large to prevent the dragging of refuse therewith, adjustable means rigidly attached to said carriage and having stop means engageable with said reciprocatory member to adjustably limit the maximum reciprocation stroke length of said reciprocatory member, and spring means continually urging said reciprocatory member for engagement with said stop means.