Now is a Great Time to Lime

Chris Penrose, Extension Educator, Agriculture and Natural Resources

Soil acidity should be corrected prior to fertilizer application, making now a great time to apply lime before a fall fertilizer application.

Here in Southeast Ohio, we have had three good chances at making hay and once you have finished, it may be a great time to either fertilize or lime fields. Proper use of lime and fertilizer is important for improving crop yields. After 32 years of helping farmers with soil tests in this part of the state, the majority are low in phosphorus and pH. I recall working in Seneca county a field that had a pH of 8.2 but many of the unglaciated regions of the state have acid soils that can use lime. To optimize production, soil acidity should be corrected prior to fertilizer application. The key is to have a soil test and determine needs.

That makes the fall and right now great times to lime fields. If we lime in the fall, there is plenty of time for the lime to react with the soil so we can fertilize in the spring. If we lime now, we can fertilize this fall if needed. Adding lime supplies calcium and magnesium, will increase soil pH and the availability of nutrients, and increase microbial activity.

Not all lime is created equal. Liming materials are labeled based on their effective neutralizing power (ENP), so the higher the number, the more effective the material will be (aglime is the reference lime and has an ENP of 2000 lbs/ton). Also, particle size plays a role as well. The finer the lime, the faster it will react. Larger particles dissolve slowly, affecting pH over a longer period. So consider these factors when pricing lime.

One common way lime is spread is via a large truck and the gentleman that spreads for me likes it more when the field has been recently mowed to better see obstacles. If I can get my fields limed now that I am done making hay, I hope to fertilize them in the early fall and maybe stockpile some fields for grazing late fall or early winter.

Quite often, I see soil tests recommending multiple tons of lime needed per acre. When it is more than two tons per acre, I often recommend applications over multiple years. Increasing pH works on a logarithmic scale so it takes ten times the lime to get from a pH of 6 to a 7 as it does to get from a 5 to a 6. So if money is an issue, spreading less lime over more acres but doing it over multiple years might be a better option, especially if your pH is closer to 5.

One last lesson I learned about liming. I was rotary mowing a field with the old tractor trying to finish before the lime spreader arrived, and he was early. I finished up after he had spread the lime and when I got back to the house, the green tractor was white and I was completely white except for my red eyes. I won’t make that mistake again!