The objective of this project is to evaluate the effects of fertilizer sources with and without magnesium (Mg) on a Penncross creeping bentgrass fairway. A potassium (K)-Mg-sulfur (S) fertilizer (K-Mag^®) and a fertilizer blend without Mg were applied to a Penncross creeping bentgrass fairway at 0.25 lb nitrogen (N)/1,000 ft², every two weeks for five months. The plots were mowed twice a week at 5/8 in. and irrigated daily at 0.1 in. Visual color and quality ratings were taken from late May to early October. Grass clippings were harvested on June 22 (13 days after fertilizer application), August 13 (12 days after fertilizer application) and September 18 (15 days after fertilizer application).