Our story

Producers of Calphos, from the Ocala deposit.

Canton Mills, Inc., also known as Manko Co., produces colloidal soft rock phosphate in Ocala, Florida. We are not a reseller. We mine it, mill it, and ship it ourselves, and we have done it for decades.

Ocala, Florida

Green crop rows stretching to the horizon

The deposit

A cleaner phosphate, decades in the making.

Our unique sourcing is the reason Calphos is notably purer than comparable products, with significantly less silica. We mine our colloidal phosphate from the original tailing ponds created during hard rock phosphate mining in the 1940s. Those historic deposits yield one of the cleanest and most consistent phosphatic clays available in our region.

That comes down to two things: where the material is mined, and the process we use to dry, pulverize, and granulate it.

A trusted name in the literature

For decades, this is the Calphos referenced in respected agricultural and organic farming literature. Influential authors such as Eliot Coleman, in The New Organic Grower, and Carey Reams have written about the benefits of this material, reinforcing its longstanding reputation among growers focused on soil health.

What we stand for

Purity, consistency, and the long view of soil.

Purity first

We hold to a single, trusted deposit and a proprietary process so every ton meets the same high standard.

Long term over short term

Calphos is for growers who prioritize lasting soil improvement over a quick, soluble spike that washes away.

Dependable supply

Licensed in most states and shipped nationwide by truck and rail, in the volume your operation needs.

Grow with the source.

Buy Calphos direct from the people who produce it. Let us help you land on the right grade and freight.

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