mg/kg humates, whereas greatest leaf areas occurred in potting mixtures containing 500
mg/kg humates. The dry weights of shoots of tomato seedlings grown in mixtures
containing 200, 250, and 500 kg/mg humates were 47.0, 37.4, and 43.4 %, respectively,
greater than those of seedlings grown in Metro-Mix 360 controls. The dry weights of
roots of tomato seedlings, grown in mixtures containing 250, 500, and 1000 mg/kg of
humates from pig manure-vermicompost, were 77.5, 79.3, and 72.1 %, respectively, more
than those of seedlings grown in the controls with no humates. These effects of humates
on growth all occurred when the plants were supplied with all their required nutrients
(Atiyeh et af. 2002). In later experiments, humates extracted from cattle, food and paper
waste vermicomposts produced similar growth increases on peppers and strawberries