A fertilizer with equal amounts of nitrogen (the first number in the 3 numbers of the fertilizer analysis) and potassium (the third number) and little or no phosphorus (the middle number) can be used on lawns and many kinds of trees, shrubs and flowers. An example of such a fertilizer would be a 15-0-15 analysis. Be sure not to apply any “weed and feed” type fertilizers to anything other than lawn areas.