News March 2019

How one Montana family keeps its seed potato crop clean

When it comes to finding quality potato seed, the supplier’s reputation is everything. And Kimm Seed Potatoes, located in Manhattan, MT, has one of the best. It’s widely recognized as a reliable producer of healthy, disease-free seed.

That reputation comes in part from how closely it works with the University of Montana’s seed certification program. The U.S. has a crazy quilt system of potato seed certification programs. Each operates on its own rules, which inevitably means some programs have a higher reputation than others.

Montana’s program ranks at or near the top in the U.S., according to various consultants and Extension agents.

The certification program helps, but Kimm Seed Potatoes also earns its stellar reputation through its culture and meticulous production methods.

Kimm Seed Potatoes grows first (G1), second (G2), and third (G3) generation potatoes and primarily sells G2 seed to other seed providers. To have healthy seed to sell, the Kimms begin with careful handling in growing G1 seeds.

G1 fields take up about 35 to 40 acres of the farm’s 1,400 acres. But they start with the nuclear plots. The Kimms hand cut seeds and place them in hand-planted lots.

Each nuclear plant has about 50 to 60 G1 plants. A team from Montana State University (MSU) comes in and begins sampling and testing.

“We’ll test 20 leaves [from each G1 group],” says Bill Kimm, Co-owner.

The farm places numbered flags in the field to track where each sample was taken. If any of the samples come back positive, the crew will not only remove the potato plant, but all 50 to 60 plants that came from the original.

“That’s very important,” Kimm says.

Some plants will express the disease more quickly than others. So even if just one plant in a group comes back positive, there’s a chance the disease hasn’t yet expressed in the other plants.

“That’s being fussy,” Kimm says. “But the farmer has to be fussy, and the people picking the leaves have to be fussy. The kids picking in the fields getting the numbers mixed up can defeat the purpose of the testing.”

Luckily, Kimm says everyone he’s worked with from MSU has been excellent. The G1 groups are the most heavily tested in order to reduce the likelihood of disease outbreaks in future generations. Yet, each generation is still tested.

From time to time, Kimm says, you have challenges that come along. And when it comes to disease or insect pressure, answering the challenge requires more than a pesticide.

For example, the Kimms moved one seed plot into an entirely new area, about 10 miles from the valley the family had used for years.

“We had more aphid pressure, so we put it in an area where no other potatoes are around,” Kimm says. “It’s more work, but it’s important to keep our seed lots clean.”

Another way to keep disease pressure down is to adhere to a strict crop rotation. Kimm Seed Potatoes rotates crops on a five- to seven-year cycle — seven is preferred — to keep disease exposure down.

They’ll grow alfalfa for three years, a single year of potatoes, then grow a grain for year, then back to a single year of potatoes, Kimm says.

There’s a bonus to crop rotation: better quality soil. The Kimms give their soil a boost with compost teas.

“I’d rather have G3 seed off of good soil than G2 off of poor soil,” Kimm says.

It’s important that buyers can visit the farm they’re buying their seed from, Kimm says. “They want to know where it comes from, know our program, and how we protected our crop during that particular year,” Kimm says.

“When we sell seed, it’s very important we’re in touch with those buying from us, and that we follow up to make sure they’re happy with us.”

Article published by Growing Produce. Go here to read the full article