Fertilizer Labels and Calculations

We will learn- How to read labels How to calculate amounts of fertilizer needed for an area

Fertilizer labels Some information is required by law to be on the fertilizer bags: Net Weight Brand and grade of fertilizer Guaranteed analysis of each nutrient in fertilizer Name and address of manufacturer

Other valuable information Some manufacturers add the following on the bag as well: % of water insoluble nitrogen Potential acidity Salt index Source of carrier % of minor elements Calculation rates How to calibrate spreaders

How much fertilizer? We have a grass lawn that needs to be fertilized and Jake has found a bag of in our garage. If we need to put 1 pound of nitrogen per 1,000 sq ft of our 16,725 sq ft lawn, how much fertilizer do we need to apply?

How do we figure this problem out? Total Fertilizer Needed =

How much Phosphorus has been applied? Assume we are applying it at the recommended N amount P= Recommend N rate X% of P in % of N in fertilizerfertilizer Can figure K amount the same way!

How much to feed plants Vegetables For a 60ft row 2 ¾ cups to 4 ½ cups ½ early in season Repeat 4-6wks later Bulbs Amount per plant 1tbsp – 2 ½ tbsp When leaves emerge Roses Per plant 4 ½ tbsp – ½ cup 1/3 at new growth After every bloom Deciduous tree/shrub 100 ft 2 under leaf canopy 4 ½ tbsp – ½ cup 1/3 when new growth Repeat twice at 6- week intervals

More plants… Lawns Per 1,000 sq ft 1 pound/ 1,000 sq ft Feed 3 times per year Evergreen tree/shrub and rhododendrons Per 10 sq ft of canopy 3 tbsp – 1/3 cup Feed half at bud swell Repeat after deadheading Flowering Perennials Per plant ¾ cup – 2 cups Half at new growth, then in 6 wks Flowering Annuals Per 100 sq ft 1 ½ cups – 2 2/3 cups At planting, then in 6 wks