Agronomic Services

Crop Fertilization Based on North Carolina Soil Tests

Table 2.3  Information required to calculate lime and fertilizer rates
Forage Crops
Crop	Target pH *	N §	P2O5 †	K2O †	Cu ‡	Zn ‡	B ¶	Mn ¥	See Note
Alfalfa, establishment	6.5	10–30	7	9	$	$	3.0	B$	12
Alfalfa, maintenance	6.5	0	14	10	$	$	2.0	B$	12
Common bermuda/ Bahia	6.0	100–150	14	14	$	$	-	B$	12
Bermuda pasture, establishment	6.0	60-80	14	14	$	$	-	B$	12
Bermuda pasture, maintenance	6.0	180–220	15	7	$	$	-	B$	12
Bluegrass	6.0	100–120	15	14	$	$	-	B$	12
Bluegrass/ White clover	6.0	0	15	14	$	$	-	B$	12
Clover/ Grass, establishment	6.5	10–30	7	7	$	$	-	B$	12
Clover/ Grass, maintenance	6.5	0	14	9	$	$	-	B$	12
Fescue/ Orchard/ Timothy, establishment	6.5	50–70	14	18	$	$	-	B$	12
Fescue/ Orchard/ Timothy, maintenance	6.0	100–200	15	14	$	$	-	B$	12
Gamagrass	6.0	180–220	15	14	$	$	-	A$	12
Legumes, misc.	6.0	0	20	19	$	$	-	B$	12
Prairiegrass	6.0	120–200	18	15	$	$	-	A$	12
Sudangrass/ Sorghum/ Millet/ Red crabgrass	6.0	140–180	15(16)	9	$	$	-	B$	12
Sudangrass/ Sorghum silage	6.0	180–220	14(16)	9	$	$	-	B$	12
Switchgrass	5.5	120–160	18	15	$	$	-	B$	12
* This target pH applies to mineral soils only. § For nitrogen, units are lb/acre, unless a § symbol follows the number, in which case units are lb/1000 ft². † These numbers refer to the equations that should be used to calculate amounts of P2O5 and K2O needed. If the crop is growing in organic soil, use the equation number in parentheses. Equations are given in Table 2.4. ‡ For copper and zinc, “R” stands for “rate” in lb/acre. For copper, the rates are 2 lb/acre for mineral soils, 4 for mineral-organic, and 6 for organic soils. For zinc, the rates are 6 lb/acre, if broadcast, and 3 lb/acre if banded. The “$” indicates that the need for copper or zinc is less certain and refers you to the $ Note: Secondary Nutrients and Micronutrients. ¶ For boron, rates are given in lb/acre. ¥ For manganese, “A” and “B” refer to the equations for calculating the manganese availability index: Equation A.    Mn-AI = 101.2 + 0.6 × Mn-I – 15.2 × pH. Equation B.   Mn-AI = 108.2 + 0.6 × Mn-I – 15.2 × pH. “R” refers to the “rate” of 10 lb/acre; “$” refers to the $ Note: Secondary Nutrients and Micronutrients.
Hardy DH, Tucker MR, Stokes CE. 2013. Crop fertilization based on North Carolina soil tests. Raleigh (NC): North Carolina Department of Agriculture and Consumer Services, Agronomic Division. Circular No. 1.