Inoculants 101: Everything Farmers Need to Know About Inoculants

To help improve crop quality, farmers are turning to inoculants.

This guide includes the following sections:

• What Is an Inoculant?

• What Are Inoculants for Pastures and Crops?

• Why Do Farmers Use Inoculants?

• 3 Types of Inoculants

• When to Apply Inoculants

• How to Apply Inoculants

• How to Assess If the Inoculant Is Effective

• Buy Inoculants from FBN®

What Is an Inoculant?

An inoculant is a beneficiary microorganism applied to either the soil or the plant in order to improve productivity and crop health. The inoculants definition can also include other kinds of microorganisms that help improve product quality and production, such as in silage and dairy products.

The global agricultural inoculants market was $522.7 million in 2024, and it is predicted to reach $898.1 million by 2033 because these beneficiary microorganisms are a reliable alternative to synthetic fertilizers and help improve plant productivity. North America holds the largest share.

What Are Inoculants for Pastures and Crops?

The inoculant is a bacteria (rhizobium species) that is applied on the seed or in-furrow with a legume crop or forage. Growing as nodules in the roots of the crop, the rhizobium has a symbiotic relationship with the plant. It fixes the atmospheric nitrogen into the soil for the developing plant to uptake, and, in return, it acquires some of its own needs from the host plant.

There are various species of rhizobium bacteria. Each legume has a specific sub-species of rhizobium it works best with.

Additionally, there are other kinds of fungal inoculants that can help with the availability of nutrients. For example, another kind of inoculant could help boost phosphorus uptake under higher pH conditions in soil while yet another can help aid nitrogen fixation in cereal and oilseed crops.

FBN offers the following inoculants to help Canadian farmers with nitrogen fixation in their pulse crops:

• Inject N, which includes the bacterium rhizobium leguminosarum, for peas, lentils, and fava beans (also known as faba bean or broad bean) comes in a liquid and granular form.

• Inject N, which includes the bacterium bradyrhizobium japonicum, for soybeans comes in a liquid and granular form.

Why Do Farmers Use Inoculants?

Farmers may use inoculants to improve both crops and silage.

Crops
Inoculants make nutrients more readily available and help improve crop health overall. They also help farmers save on nitrogen fertilizers.

Silage
Inoculants help improve the fermentation process, preserving silage quality — for example, the dry matter and protein content — for longer. They can also help with silaging at higher moisture. Furthermore, inoculants help to reduce the cost of supplementary rations.

3 Types of Inoculants

Here are three common types of inoculants used for seed:

1. Peat
Peat is one of the common types of inoculant in pulse crops and can be applied on seed. It’s considered to be an excellent inoculant option.

2. Granular
Granular inoculant is the most popular inoculant type for pulse crops in the Canadian Prairies. It is applied in-furrow very close to the seed. Granular works well even under relatively dry weather conditions.

3. Liquid-Based
Liquid-based inoculant is common for pulse crops. This inoculant type can be applied on the seed and works well under moderate moisture conditions.

When to Apply Inoculants

Inoculants should be applied when seeding a legume crop. It’s highly recommended to apply it as close as possible to seeding time. Sometimes, inoculant comes with the forage seed, but it may need to be bought separately if you are seeding a pulse crop depending on the product.

Research has also shown that sites with no previous soybean history have a strong yield response to dual inoculation in which liquid inoculant was applied on the seed and granular inoculant was applied in-furrow. Indian Head Agricultural Research Foundation’s three-year study showed an average yield increase of 7.4 bushels per acre or 24%.

How to Apply Inoculants

There are multiple methods of applying inoculants, with application placement dependent on formulation type. Always follow the product labels. Compatibility recommendations may vary if applying with other seed treatments or products.

Peat Inoculant
Prepare a slurry with the peat inoculant and apply it on the seed, mixing it well. Alternatively, apply it to the seed being augered to the seeder tank. Another option is to apply a small amount of moisture to the seed, add the peat inoculant, and mix them well in the hopper of the planter.

Granular Inoculant
Granular inoculant goes in a separate tank in the air drill to ensure rate accuracy. Apply as close as possible to the seed at the recommended rate based on the row spacing.

Liquid Inoculant
Liquid inoculant is applied using the same method as seed treatment. Apply it while augering the seed to the truck. Water can be added, but always ensure the seeds are dry by the time they get out of the auger. Too much water can result in seed clumping. Using a multi-nozzle system on the auger is recommended.

How to Assess If the Inoculant Is Effective

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