Chemical fertilizers get the job done, but they are not the best thing for the environment. If it is possible for you to create an organic liquid fertilizer, you should do it. One way to make an organic liquid fertilizer is to create what is known as "manure tea." This may sound gross, but it is one of the best fertilizers you can make for your lawn.
Shovel manure into pillowcases until you have 10 pounds worth.
Fill one bucket with water for each pillowcase. Let the water sit out for 24 to 48 hours so that all the chlorine leaves it.
Put the pillowcases into the buckets and set them aside for one month. If you want to put lids on the buckets, you can. Just make sure you poke holes in the lids so air can get to the manure tea.
Remove the pillowcases and pour the manure tea into a garden sprayer. Spray across your lawn.