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Primo R1

Super Concentrated Soybean Inoculant

Are your soybeans tired, sad, puny? It could be a lack of Nitrogen. A soybean plant needs five pounds of Nitrogen per bushel, but many plants don’t get the amount they need to grow. Using an on-seed inoculant for soybeans helps your plants build a larger “nitrogen engine” to support greater yield potential. A soybean inoculant helps ensure the right type and number of bacteria are present to help your soybeans produce nodules, which will then generate Nitrogen.

Primo R1 is a super concentrated soybean inoculant that helps provide soybean plants with the levels of rhizobia required to produce the nitrogen it needs. Imagine the benefits of incorporating this inoculant into your soybean seed treatment process!

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It’s not just the high-quality, high-concentration formula that makes Primo R1 a preferred soybean inoculant. The easy FlexConnect application also sets it apart. Primo R1 is applied with a single-bladder, single-hose, single-cap system, so you can be up and running in minutes with no hassle. FlexConnect application also means you get a more consistent inoculant amount on every seed for a better yield from the first unit treated to the last, even if it’s over a 14-day period!

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• Greater than 2.6M Colony Forming Units per seed to better outcompete less effective background rhizobia

• Multiple Strains for more consistent performance

• Up to 2X the amount of rhizobia per soybean seed than competition

• Single bladder product for more convenient handling

• Only a 0.625 fl. oz./140k seeds (1.25 fl oz per cwt) application rate


• Offered in 40 or 500 unit bladder sizes for traditional application

• Offered in 200 or 800 unit bladder sizes that are compatible with FlexConnect

• Using Primo R1 coupled with FlexConnect gains operational efficiencies and agronomic benefits by providing consistent, high-quality soybean inoculant on every seed

Still trying to figure out what all this bacteria, Nitrogen, and inoculant stuff is about? Check out our FAQs below for answers.

Frequently Asked Questions About the Primo R1 Soybean Inoculant

Why use the Primo R1 soybean rhizobium inoculant?

It takes four to six pounds of Nitrogen to produce a bushel of soybeans. A variety of factors can lead to your soybeans not getting the Nitrogen they need to thrive, but with a soybean inoculant, your plants get the optimal Nitrogen levels to support greater yield potential.

How do soybeans get Nitrogen?

Soybeans naturally get Nitrogen from:
• Organic sources
• Residual sources leftover from previous years
• Nitrogen-producing bacteria (rhizobia)

The latter is a symbiotic relationship between the soybean and rhizobia. The soybean produces nodules to house the rhizobia and provides carbohydrates that feed them. They then produce Nitrogen that feeds the soybeans.

Why do we have to inoculate our soybeans every year?

Soybeans need Nitrogen to grow, and rhizobia are the best way to provide it. A number of things can reduce the amount of background rhizobia in the soil, such as flooding, extreme hot or cold weather conditions, and soil pH levels. Not only can rhizobia sometimes be scarce, but the key is to have the right rhizobia present for your soybeans to help with nodulation and Nitrogen production.

That’s why we need a regular inoculant application when planting — to ensure that the right amount of the right rhizobia is there. An inoculant for soybeans helps rhizobia and soybeans work together to produce the Nitrogen soybeans need.

I’m on a two-year rotation. Do I really need to inoculate my soybeans?

Fields vary year-round — high ground, low ground, high pH, low pH — so there’s no reliable way to know if the right bacteria is in the soil or if it’s in the right quantity. For less than a bushel per acre, however, you can ensure that you get the right type and amount of rhizobia to enable your soybeans to produce as many nodules as possible to generate the Nitrogen they need.

What does “the right type of rhizobia” mean?

Not all rhizobia are the same. You may have some residual rhizobia in your field, but it could not be the best at producing the amount of Nitrogen required by soybeans to produce maximum yields. Using an inoculant for soybeans when you plant helps provide the best possible Nitrogen-produce rhizobia.

Does an inoculant provide bacterial consistency across your field?

Yes. Primo R1 coupled with FlexConnect enhances operational efficiencies and agronomic benefits by providing consistent, high-quality soybean rhizobia inoculant on every seed across your field.

Are there other benefits to a soybean inoculant?

Yep. Soybean inoculant also helps produce efficiencies within the plant, like improving general appearance and health, better utilizing the Phosphorus and Potassium available to the plant, and fighting off stressors. When plants are properly nourished with the right nutrients, they’re more resilient to drought and other extreme weather conditions and produce an all-around better yield.

How do you produce top-yielding soybeans?

It’s proven that a soybean rhizobium inoculant increases soybean yield. Plenty of products say they’ll help produce higher yields, but the most overlooked strategy is a simple, biological inoculant like Primo R1. Primo R1 is a multi-strain Bradyrhizobium japonicum soybean inoculant. It includes more higher-powered rhizobia to out-compete background soil populations. That sounds complicated, but it’s really a quite simple, smart product. The point is, start simple and don’t underestimate how powerful a biological soybean inoculant can be.


Looking for more information on our family of Primo products?

  • Primo Power CL is a higher concentration liquid, in-furrow peanut inoculant
  • Primo GX2 is an in-furrow, multi-action granular inoculant

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