The research was carried out from January to December 2015. Seeds were collected from ripe fruits of the mother plants at the age of 8 years and older. The harvested fruits had to be immediately processed to remove impurities, floaters, and keep good seeds for sowing or storing. The best harvesting period was from the latter half of April to the end of May. Results from sowing Cassia fistula showed that the hot water (80-100oC) could bring the highest germination rate. Results from monitoring influence of potting mix on Cassia fistula's growth showed that height growth, root collar diameter and garden exporting got the highest performance with fertilizer formula 99 percent land + 1 percent NPK.