Match seed drop to soil

Planting exactly the right amount of seed in the right soil is a big deal to Rich Schlipf, Milford. When it comes to planting, he’s all about planting the number of seeds per acre he thinks the soil can handle. And he’s also all about giving every seed he plants the best environment possible.

Key Points

Return on investment means matching population to soil for this farmer.

There’s a faster payback for variable-rate equipment where soils are more variable.

Changing seed count by 1,000 kernels per acre is about a $2.50 shift either way.

Full disclosure: Schlipf sells equipment for Precision Planting, Tremont, Ill. But after spending half a day with him, it’s easy to imagine he would be taking the same steps to get things right, whether he helped other farmers or not.

Best return

It’s not every farmer who talks about return on investment, or ROI, in his barn lot, looking over his planter. Most save that for the office. But to Schlipf, ROI is what planting is all about.

“I’m looking for the biggest return on investment I can get from my crop,” he says. “I believe I do that when I plant the population that the soil can best support. That’s why I’m a firm believer in changing seed rates on the go.”

Since he has a variety of soils, sometimes within the same field, he believes changing rates is especially helpful. His planter is set up to vary rates according to a predetermined computer map using GPS.

His seed drop in corn typically varies from 28,000 to 36,000 seeds per acre, he notes. It changes populations in increments of about 2,000 seeds per acre.

He’s also saving money by dropping back the seed count on soils where he just can’t justify higher populations.

For example, if seed costs $2.50 per 1,000 kernels ($200 for 80,000 kernels per bag), and he set the planter at 32,000 seeds per acre in that field if he picked one rate, then he’d save $10 per acre in seed costs alone where he only drops 28,000.

Seed economics

Suppose that you can only pick one rate for a productive field, and you go with 32,000 seeds per acre. Again, Schlipf’s example shows you’ll spend $10 less per acre if you can drop back to 28,000 where you think 32,000 is too many. That $10 savings doesn’t account for yield loss that might occur from overpopulation in a dry year.

What about on the good soils, where you kick it up to 36,000 seeds per acre? How many more bushels per acre do you need to pay for the extra seed?

At the same $2.50 per 1,000 seeds, that’s $10. At $5-per-bushel corn, you only need a 2-bushel-per-acre increase to pay for the extra seed. Of course, that doesn’t count the cost of the equipment that allows you to vary rates on the go. That’s an investment that would be spread over time.

Being able to kick up rates in good soils allows Schlipf to take advantage of favorable conditions in good years. An extra 1,000 plants can amount to an extra 7 bushels per acre, agronomists say.


Think right rate: Planting at the right rate to match the soil is a matter of protecting his return on investment, Rich Schlipf says.

This article published in the March, 2011 edition of INDIANA PRAIRIE FARMER.

All rights reserved. Copyright Farm Progress Cos. 2011.