Content ID


Inventing a new closing wheel

If you search the internet for “planter closing wheels,” you’ll find every shape and size of aftermarket options, ranging from solid wheels made of cast iron to wheels with fingers or tines to serrated disks.

However, when Tony Wendler started looking for an option to replace the rubber closing wheels on his John Deere planter, he felt a little like Goldilocks trying to find a comfortable bed.

“The hard rubber wheels can pick up mud if our soils are too wet, and they can pack the sidewall when it really needs to be loosened up for better seed-to-soil contact,” says Wendler, who farms near Armstrong, Iowa.

“Yet, many of the spiked wheels that I found had the potential to either overpenetrate or they would get too aggressive and throw seeds out of the furrow, especially if you went too fast. Another problem was that the void between the spikes on some models could pick up and hold a rock. Others were made of poly, which wears out rather quickly.”

So, with the help of his son, James, who owns a fabricating company in Des Moines, Iowa, Wendler set out about seven years ago to design his own closing wheel. After testing a few variations and working with the agronomists at Beck’s Hybrids, he finally settled on a design that combines spikes with a depth ring.


Unlike other closing wheels, Wendler’s design, which he calls the Germinator, consists of two layers of steel stacked.

Each layer is made up of three pieces to reduce waste. (Each piece is also laser-cut from grade 50 steel.) To reduce wear, the extra weight of the steel helps reduce down pressure needs in heavy soil and no-till conditions.

“I hold the provisional patent on the design, and James and I hold the provisional patent on the manufacturing process,” Wendler says, pointing out how the wheel components fit together like jigsaw puzzle pieces to form a perfect circle.

In contrast to some other designs, the curvature between the teeth widens out so it sheds wet soil and any rocks it encounters. In the meantime, the inner wheel, which is welded into place against the spiked wheel, acts as a depth gauge, while firming the soil around the seed.

“We’ve tested it at speeds up to 12 mph and haven’t found any place that the seed was thrown out of the row. In every case, the seeds have been lined up in the bottom of the furrow.”

Builds Them Himself

Rather than sell his design, Wendler has begun manufacturing and selling the Germinator under his own company, Farm Shop Mfg., LLC (

Customers can buy the closing wheel to replace current rubber wheels, using the existing wheel assembly and bearing. Or they can purchase the entire wheel assembly, which includes new plastic closing wheel rims, bearings, and bolts. Pending no increase in steel prices, the cost of the closing wheel alone is $65.

Wheel assemblies list for $25 each or $90 when purchased as a complete closing wheel unit that includes the spiked closing wheel.

In the meantime, Wendler has been working with stores and dealerships to expand the market beyond his own mail-order business.

“We stock wheels for every brand except the Case IH planters that use a single closing wheel. On most planters, the ring-only insert option simply installs on the factory wheels.”

Wendler’s creative mind hasn’t been content to just settle on a new closing wheel design, though. He also has developed a new grain-temperature sensing system that links to a weather monitor, which will allow producers to remove moisture from corn or add moisture to soybeans for higher market value.

Read more about

Machinery Talk