Components

• The most important components in fertilizer are nitrogen, phosphorus and potassium; the percentages of these ingredients are labeled on the package as a series of numbers, such as 18-6-12. Nitrogen is the most important ingredient.
  
  

Benefits

• Fertilizing your lawn can help prevent disease, improve its ability to withstand stress, and improve its color.
  
  

Time Frame

• Fertilizer is most effective in the fall. You can also fertilize in early spring.
  
  

Considerations

• Fertilizer can be dangerous to children and pets and can also pollute the water supply. Using fertilizer incorrectly can also damage your grass.
  
  

Safety

• Wear goggles, a mask, rubber boots, long pants and a long-sleeve shirt when you are applying fertilizer. Do not apply fertilizer on a windy day, and sweep up extra fertilizer off driveways and other areas. Keep people and animals off the grass for at least 24 hours.