Soil Test (#E2D5AE)

Asked May 13, 2015, 9:43 PM EDT

The personal recommendation states I need to apply 0.3 lb. phosphate (P2O5)/1000 sq. feet. This number seems low especially since the examples of what fertilizers to use show higher values. For example, in first recommendation it states - two applications of 18-24-12 would deliver 2.6 lbs. P2O5 which would meet the P recommendations for the lowest soil test P level. This 2.6 lbs is a LOT more then the originally suggested 0.3 lbs. Is there a typo in the original recommendation? Thanks

Oakland County Michigan soil and fertility issues

1 Response

Although your soil test states that you only need .3 lbs of actual (100%) phosphorus, increased amounts of phosphorus are required when establishing a new lawn since the young grass roots are unable to uptake the phosphorus available in the soil. Since you also need additional potassium, I would go with Option #3 and apply a balanced fertilized until your lawn is established. Once the lawn is established, it will probably be easier to apply a winterizer fertilizer (high in potassium) with zero phosphorus. This is readily available. You can then apply the small amount of phosphorus that you need independently using super phosphate (0-20-0) or super triple phosphate (0-46-0). Retest the soil after 3 years. The numbers on the fertilizer stand for the percent of that ingredient. 18-24-12 has 18% nitrogen, 24% phosphorus, and 12% potassium. .3 pounds of phosphorus translates to 1.5 lbs of super phosphate (0-20-0) or or .6 lbs of super triple phosphate 0-46-0 per 1000 sq. ft.