Adding fertilizer to increase the nitrogen content of a pile is wasteful and expensive. Many gardeners with a high proportion of acid-rich materials mistakenly add lime to their pile to produce compost with a balanced pH. Unfortunately, adding ground limestone will turn your compost ecosystem into an ammonia factory, with nitrogen rapidly lost as a noxious gas. Finished compost is almost always slightly alkaline naturally. A properly built and managed compost pile should smell like the humus-sweet duff of a forest floor. Rodents and Pests.
Compost piles almost never attract pests if they contain only yard trimmings.
Adding food to a pile increases the attractiveness somewhat, but only if managed improperly, such as dumping scraps on the top of a pile or bin. Urban composters might want to avoid adding food altogether or use a worm box or a completely enclosed design. Meanwhile, compost piles fall well behind birdfeeders, outdoor pet food bowls, pet feces, and trash containers as residential causes for rodent activity. Adding different types of material to a compost pile in varying proportions is appropriate only if all of the materials are on hand at one time, which is seldom the case. Mix, stir, and fluff for a hard-working compost stew.