As we investigate what inputs we can reduce or leave out, lime to reduce acidity is not one of them. Table 3-4 in 2026 Peanut Information demonstrates the value of growing peanuts at a pH of 6.0. In that table, when gypsum is applied at a 1X rate, yield increases by 26% when pH is raised from 5.6 to 6.0. This is due in part because of the positive impact lime has on reducing soil acidity, but also because we often do not see a positive response to gypsum when soil pH is low. We get a positive response to lime when we move the pH up to 6.0. The only way we get a positive response to gypsum is to have soil pH at the recommended level (6.0 or greater.)

For example, if yield is 4,200 pounds per acre and price is $450 per ton ($0.225 per pound), a 26% difference in yield is 1,092 pounds per acre or $246 per acre. Based on our budgets (Table 1-4 for Virginia market types in conventional tillage), 0.5 tons lime/acre (prorated) is $41 per acre. Gypsum is an additional $21 per acre (0.6 tons per acre at a cost of $35/ton.) Let’s assume the gypsum price is lower than what some growers end up paying. Call it $40 per acre. And let’s assume you don’t prorate lime over multiple crops (seasons.) Call it $82 per acre. The combined cost of lime and gypsum in this example is $122 per acre. Based on our research findings (Table 3-4), there is still a $124 per acre financial return on the investment in lime and gypsum. This also considers pod yield only. Market grades (total sound mature kernels and extra-large kernels) almost always increase when gypsum is applied. The $246 per acre increase with lime and gypsum is likely lower than what the increase would be if we considered market grades.

Let's say the yield increase is more modest from lime and gypsum. Use 15% increase in yield (630 pounds per acre.) This is $142 per acre increase with lime and gypsum. The economic return is $20 per acre (142-122.)

If the yield is above our state average of 4,200 pounds per acre, the return on lime and gypsum investment increases substantially.

All acres of Virginia market types need gypsum, even at a $450 per ton contract.

Soil acidity needs to be addressed, even at a $450 per ton contract.