March 07, 2021

Farmer shares variable rate seeding, fertilizer insight

9 tips and observations

BOWLING GREEN, Ky. — Choosing seeding and fertilizer rates for variable-rate applications can be challenging, but the potential cost savings and improved yields make it worthwhile, said farmer Mark Chapman.

Chapman writes all the prescriptions for his no-till farming operation and has developed a systematic approach to setting seeding and fertility goals.

He discussed variable rate programs at the National No-Tillage Conference.

“Developing a successful strategy begins with asking good questions,” Chapman said. “There’s so much information available, it begins with knowing what you want to do with variable rate.

“The first question is, what are my goals? Depending on the answer, it will affect how you go into variable rate.

“For example, is it because I have a limited budget and I need the biggest bang for my buck for the fertilizer or seed dollars I have? Perhaps my goal is to push yields.”

In 2008, Chapman’s goals were to reduce fertilizer costs, address pH variation in the field, improve low-yield areas if possible, see inputs applied more effectively for a more profitable return, and grid management.

From 2012 to now, his goals have changed.

He aims to apply lime to maintain 6.4 to 6.8 pH, establish profitable fertility levels for each field by management zones, variable rate P and K based on crop removal to maintain fertility levels, and place fertilizer and seed where profitability of a return is the greatest.

Tips And Observations

Chapman also shared nine things he’s learned on his journey.

1. Write a prescription for all varieties on each field.

2. Leave flat rate passes in the field as a check strip comparison.

3. Many planters are capable of planting hybrids with different seeding rates simultaneously.

4. Make the multi-hybrid planter decision.

5. Vary the path of the fertilizer application from year to year.

6. Variable rate applications can improve trouble areas in the field.

7. No-till raised yields on the average to below-average regions in the field.

8. Variable rate strategies raised yields on the average to above-average regions in the field.

9. Enjoy the journey.

“You’ll find out things about your farm that might surprise you,” Chapman said. “It’s pretty exciting to try a new idea and be rewarded for it.

“I enjoy getting more efficiency out of fertilizer and seed dollars by getting the right thing in the right spot. It’s not hitting the bull’s-eye. It’s just consistently being on the target, increasing the probability of a return.”

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Erica Quinlan

Field Editor