Response of citronella grass on several phosphate levels application at andosol

Currently, the cultivation of citronella grass (Cymbopogon nardus L.) is widely developed in highland areas dominated by Andosol soil. Andosol possesses low phosphorous availability, strongly bound to Al and Fe. This research was aimed to examine the effect of P fertilizer on C. nardus L. at Andosol. The research was conducted from June 2014 to August 2015. Phosphate fertilization stimulated plant growth, yield and oil quality of citronella grass on Andosol. The most suitable Phosphorus dosage at 1.08 g plant⁻¹ (10.8 kg ha⁻¹) produced high total fresh herb yield and oil quality of citronella grass. Total fresh herb yield increased 21.2% (3.4 kg plant⁻¹ year⁻¹) compared to control. Whereas citronella content, oil content and oil yield were 35.2%, 1.64% and 1.27% respectively. The phosphate residue in Andosol can be potentially utilized for the next planting season.