Apply an all-purpose liquid plant fertilizer once per month as long as the stems remain green. Use only the amount specified on the bottle and use care not to overfertilize.
Wait until the narcissus flowers wilt, which occurs at different times based on climate and whether the bulbs are indoors or outdoors. If planted outdoors, blooming typically ceases in the middle to late spring.
Wait six weeks from the time the blooms wilt to prune the narcissus stems. If you have an indoor plant, make sure it is in a location that receives full sunlight, which is critical during this time period.
Examine the stems to ensure that they are all either yellow or brown, which means that they are done storing food for the bulbs. Grasp the stems 1 inch above the bulb or at the soil level. Cut the stems off using the hand pruners and discard the pruned stem portions.