Spronk Seed Farm expansion meets growing demand for bulk seed

EDGERTON -- While midwestern winters send farm fields into a period of dormancy, January is anything but dormant at Spronk Seed Farm just outside of Edgerton.

Brothers Cal (left) and Harlan Spronk stand inside their newly completed bulk load out area at their seed farm near Edgerton. (Julie Buntjer/Daily Globe)

EDGERTON - While midwestern winters send farm fields into a period of dormancy, January is anything but dormant at Spronk Seed Farm just outside of Edgerton.

Now is their busy time, said Cal Spronk, who owns the business with his brother, Harlan.

Since harvest ended, the Spronks and their employees - most of whom are farmers - have been busy running seed through their facility to clean, process and package for the 2017 planting season. Thanks to an expansion project last summer, they now offer bulk seed processing.

While they work primarily with soybeans, Spronk Seed Farm cleans and processes some small grains as well, including oats, barley and, more recently, cover crop rye.

“It really works nice for us because of timing,” said Cal Spronk. “We’re busy all winter long processing soybean seed, while cover crops are harvested in middle summer and processed and planted again, so that keeps us busy in the summertime.”


As the popularity of cover crops increases, Spronk said they have dabbled in radish seed cleaning. In time, he hopes they can develop a smoother process for the specialty seed.

“We just don’t have that figured out yet,” he said with a smile.

Building the business When Cal and Harlan Spronk’s father purchased the farm site where their seed cleaning business is located in 1977, the previous owner had been involved in the seed business.

“Whenever he needed some help, he would grab one of us boys,” said Spronk, who grew up as a neighbor to the previous owner. “He eventually sold his farm to my dad and recommended we stay in the seed business.

“The history of cleaning seed on this farm goes back to the 1940s,” he added.

The Spronks did just as their neighbor encouraged, building up the business to the point of constructing a seed cleaning facility on the site in 1984.

“Back in the ’80s, we were cleaning a lot of certified seed, and of course that was before Roundup Ready,” Spronk said. “Prior to Roundup Ready, we cleaned a lot of seed just for farmers. We would do germination tests on it. It was just their seed that they grew that they liked. That was the way things happened back then.”

When traited seeds hit the market in the 1990s - RoundUp Ready, Bt varieties and herbicide-tolerant seeds - the companies that invented those traits put patents on them. It was the beginning of the end for farmers who wanted to grow their own seed.


“Our business really shifted from cleaning seed for farmers to cleaning seed for companies that hold patents on the seed,” Spronk said. “It’s just how it happened - not saying one way is better than the other.

“Now, there’s new traits coming on the market every couple of years,” he added. “With that change from cleaning seeds for farmers to cleaning seeds for companies that hold patents, we’re now working for them. They need us; we need them.

“They can invent all the traits they want, but if they don’t have a method of getting the traits into the marketplace with their seed, it doesn’t do them any good.”

Since the mid-1990s, Spronk Seed Farm has processed seed for private seed companies and worked with their distribution networks and company agronomists. Today, they work solely with Stine Seed Co.

“Our little part of the seed industry ‘big picture’ is propagating the seed, processing it and packaging and servicing their dealers,” Spronk said. His seed farm ships seed to approximately 250 dealers, though the largest volume of seed goes to about 75 dealers.

“The majority (95 percent) of seed that gets run through our plant is produced within 70 miles of here,” Spronk said. “It comes here for processing and is distributed to the dealer network - a majority within 100 miles of here.”

Smaller orders, like some from dealers in Michigan, amount to just half a load of seed cleaned per year.

Steady growth After investing in the seed processing building in 1984, the Spronks continued to grow their business. In 1995, a warehouse and four hopper bottom bins were added to the site and, two years later, a second warehouse was added onto the existing setup.


A storage bin was added in 2000, the office and bagging areas were expanded in 2005, a heated seed treating facility was built in 2011, another - larger - storage bin was added in 2012 and the overhead bulk bin project was completed in 2016.

“It seems like we’re always changing something, as my dad would say,” said Spronk.

In addition to new buildings and bins, the business also invested in a Japanese-made Harada belt sorter, a food-grade soybean processor the Spronks bought for sorting seed.

All of the additions over the years have shaped Spronk Seed Farm for the future - handling increased seed volume and being able to load and unload bulk seed.

“The bulk seed is becoming much more popular and widespread,” Spronk said, noting that as planting equipment changes, the seed industry has to follow suit.

While a lot of planters still in use today have individual seed boxes, the new bulk planters are appealing because of the savings on time and labor.

Disappearing are the days when farmers purchased all of their seed in bags and had to open each one and pour into the seed box. It’s not only time-consuming, but back-breaking work after a while.

“A lot of the dealers we ship to, there’s getting to be a good share of them that have bulk seed handling facilities,” Spronk shared. “They’ve invested in that; that’s why we need to get on board and be able to supply them with bulk seed in larger volumes.”

Prior to the bulk handling expansion at the seed farm, Spronk said they could take in and ship out two semi-loads of seed per day. Now, they can handle 10 semi loads per day.

“We had three bins and now we’ve got six more,” he said. “We’ve got nine bins, and the six new ones are bigger bins so they’ll hold more.

“Now we can clean the seed, have it set aside and they can send three trucks through back-to-back and pick up clean seed - all one lot number and variety - at one time,” he added. “In the wintertime, that’s important because one day might be good but the next day might be a blizzard. Now we can hold three semi-loads of clean seed overhead and … we can still use our existing bins to process other varieties.”

It’s made for improved efficiency as well.

Process to package When soybean seed is delivered to Spronk Seed Farm, it enters a fanning mill where any soybean pods are removed, split soybeans fall out and the seed is cleaned. From there, it enters the Harada belt sorter. There, any soybeans that are chipped or don’t roll on the belt get discarded.

The discarded seed is hauled either to an area feed mill or to Minnesota Soybean Processors in Brewster.

“The seed halves, pods and sticks end up in Brewster and get processed like regular soybeans,” Spronk said. “There’s a lot of value to that stuff.”

Meanwhile, the bounty of high-quality soybeans move on down the line to be packaged in paper bags, tote bags and bins.

Since soybean seed is sold based on count - 140,000 soybean seeds per bag - the weight of the bags vary between varieties and years. In 2016, there were phenomenal soybean yields because the seeds were much larger, thanks to optimal growing conditions. The larger seeds mean the bags of seed are heavier this year - about 70 pounds each - to meet seed counts.

“When we’re cleaning seed, we pull samples off the cleaner every hour and set them aside until we have four samples. Then we count the seeds in those four samples and average it,” Spronk explained. “We take a weighted average, and that’s how we determine the pounds that go into a bag.

“The bigger seed kind of presents a conundrum in processing seeds,” he added. “We have bags that only hold so much. Stine gave us bigger bags, but they still have a limit in how much is put in.”

Spronk predicts the bulk seed industry will continue to expand, and with its expansion complete and ready to meet those needs, Spronk Seed Farm is well positioned for the future.

Julie Buntjer became editor of The Globe in July 2021, after working as a beat reporter at the Worthington newspaper since December 2003. She has a bachelor's degree in agriculture journalism from South Dakota State University.
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