The Effects of Fly Ash and Cow Manure on Water Spinach Grown on An Ultisol of Lampung, Indonesia

Fly ash is the residue of coal combustion that can potentially be an ameliorant. Unfortunately, its use limited by government regulations are classified as hazardous and toxic materials. This study examines effectiveness fly cow manure ameliorant for Ultisols. The experiment was carried out two factors, i.e., dose ash, namely 0, 50, 100, 150 t/ha, quantity manure, 10, 20, 30 t/ha. results show could ameliorants low-pH soils such suitable in this 50 t/ha 20 respectively. Increasing amount caused a decrease growth water spinach, plant height, number leaves, fresh weight, root length, dry weight root. In addition, increased pH 6.66-7.30, total P 31.74-52.21 mg/100 g, K 16.19-25.75 g.