PERUBAHAN SIFAT TANAH ULTISOL UNTUK MENDUKUNG PERTUMBUHAN TANAMAN ROSELLA (HIBISCUS SABDARIFFA L.) OLEH PERLAKUAN KOMPOS DAN JENIS AIR PENYIRAM

The objective of this research is to know the effect of compost application and kinds of pouring water used on Ultisol, the growth and production of Rosella plant (Hibiscus sabdariffa L). The research was done on May-November 2012 in screen house and at Chemistry and Fertility Laboratory, Research and Technology Laboratory, Faculty of Agriculture USU Medan. The design used was randomized block design (RBD) which consits of 2 (two) factors and 2 replication, Factor I: Compost (K) consist of K0 = control/without, K1 =.compost of rubbish, K2 = compost of stubbles; K3 = compost of corn. Factor II: The pouring of water (P) used 3 (three) kinds: P1 =PAM water; P2= the iron of water, P3 =goat urine. The result of this research showed that compost very significantly decreased the bulk density of the soil, increased pH and plant height. The pouring water which contains Fe was very significantly decreased of pH soil and more stronger than urine compared with PAM water. However PAM water did not significantly effect to others parameter. The interaction was significantly effect to pH, plant height and production but did not significantly for BD and the content of Fe in rosella fruits.