Try a simple test. Squeeze the handful of slightly moist dirt into a compressed ball. If it easily crumbles again with a little pressure, your soil is good. To improve and lighten the soil for the best possible results, mix in a generous amount of organic peat moss or compost followed by some bone meal and commercial, packaged cow manure. Raw cow manure should be composted for about a year before using as a fertilizer.
Fresh manure can burn plants.
Top dress your established daylily beds with fresh compost and a little of the decomposed cow manure. Loosen the soil around the individual plants, working the top dressing a few inches in to the soil. Daylilies require very little care on a day to day basis in the garden. To keep your garden tidy you will want to clip any dead leaves and remove the spent flower scapes. Any seed pods that form should be removed unless you intend to grow daylilies from seed.