The researchers wanted to see how adding N-fixer bacteria to biofertilizer affects the growth of patchouli plants. They tested different N-fixer bacteria to find the most effective one, then added it to the biofertilizer. They found that the nitrogen content of the biofertilizer increased as they added more N-fixer bacteria. Using this enhanced biofertilizer led to better plant growth, with leaves and branches improving by 8% and 5% respectively compared to regular biofertilizer. To get the best results, the biofertilizer should have more than 10% N-fixer bacteria.