Fertilizer Ratings

• There are several ways to categorize fertilizers, but one of the most common is according to their concentration by the weight of nitrogen (N), phosphorous (P) and potassium (K) they contain. These values are printed on the fertilizer's labeling as three numbers. A 10-15-20 fertilizer, for instance, would contain 10 percent nitrogen, 15 percent phosphorous and 20 percent potassium by weight, respectively, with other ingredients making up the remaining 55 percent. Understanding these NPK ratings is key to choosing the right fertilizer for your plant's needs.
  
  

Fertilizers and Bell Peppers

• Peppers, in general, favor a nutrient-rich, well-drained loamy or sandy loam soil. Peppers are "heavy feeders, but they are also picky eaters," according to the National Gardening Association. In other words, peppers need lots of nutrients in order to grow healthily, but they need the right nutrients. A good 12-6-6 or 5-10-10 fertilizer will give the peppers a good nutrient-rich meal, but of course these recommendations assume ideal soil conditions. Your unique soil conditions may require a fertilizer that has higher concentrations of phosphorous and potassium; simply purchase a fertilizer with an NPK rating indicating a higher concentration of those two ingredients. The only thing to avoid is a fertilizer with a high concentration of nitrogen, as using such a fertilizer can force the pepper plant to divert nutrients to leaf-building rather to fruit-building.
  
  

Application Tips

• Timing and technique for fertilizer application can be almost as important as choosing the right fertilizer. First, add fertilizer upon planting the pepper plant along with some organic fertilizer such as animal manure mixed in. Under ideal conditions, the pepper plants will not need additional fertilization, though you should test soil to see.
  
  

Other Considerations

• Proper fertilization requires careful understanding of the ratio of the fertilizer's essential chemical components. Though in general most pepper plants require a fertilizer that is not peculiarly rich in any of the three essential fertilizer elements, some pepper plants respond well to mixtures as rich as 10-20-20. It bears repeating that fertilizer choices should be based primarily on your unique soil conditions, since feeding the pepper plants an improper blend can have deleterious effects. The best advice for fertilizer mixtures always comes from local gardening and farming experts that are familiar with the unique soil and atmospheric conditions in your specific area.