Don't. Pines enjoy a spare soil and there will surely be enough residual fertilizer from the nursery in the soil to get it through its indoor stay. Move the tree back outdoors asap when you're done using it for decoration. It will not appreciate indoor conditions, even in zone 10. When you do begin fertilizing, occasional weak doses of 24-8-16 with micronutrients is the best choice, followed by a blend like MG for Azaleas, Rhododendrons & Camellias. Pines like the soil on the dry side, so be careful not to over-nurture & water too frequently.

Al

Thanks Al! Much appreciated.