- 1). Place an empty container that will hold a quart on an accurate scale and reset the scale to zero or write down the weight in ounces. Pour exactly one quart of liquid fertilizer into the container and note the weight in ounces. Subtract the weight of the container, if you didn't reset the scale to zero. The result is the weight of one quart of fertilizer in ounces.
- 2). Find the amount of the nutrient that you're interested in on the fertilizer label. If the fertilizer has three numbers separated by hyphens, such as 4-5-4, they indicate the percentage by weight of nitrogen, phosphorus and potassium, in that order. Other ingredients may be listed as a percent in smaller type elsewhere on the label.
- 3). Multiply the percentage of the ingredient by the weight of one quart of fertilizer, to find the ounces per quart. If you're using one of the three percentages such as the 4 in 4-5-4, express it as .04 when multiplying. For example, if one quart weighs 45 oz. and it contains 4 percent nitrogen by weight, multiply 45 by .04 to get 1.8 oz. of nitrogen per quart.
- 4). Convert ounces per quart to the units you need by using the following formulas: To convert to pounds per quart, divide by 16. To convert to ounces per gallon, multiply by 4. To convert to pounds per gallon, divide by 4. Use the result to apply the correct number of gallons or quarts, depending on the number of pounds or ounces of fertilizer that you want to apply.
SHARE
