Rock Phosphate

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An organic, untreated Soft Rock Phosphate (0-3-0) with colloidal clay containing valuable trace minerals in addition to phosphorus. Since phosphorus is lacking in most soils, fertilizer applications are a must for superior results. Calphos™ contains a minimum of 3% available (and a minimum of 20% total) phosphoric acid (P2O5) and 20% Calcium (Ca). OMRI Listed for use in organic production.

Once applied, rock phosphate remains in the soil until used by the plants – will not leach. Ideal for fruiting and flowering plants, it stimulates strong root formation, hastens crop maturity and encourages earthworms and soil bacteria.

• A non-leachable source of phosphorus and calcium
• Used by growers for over 50 years
• Promotes strong roots and accelerates crop maturity
• Earthworms and beneficial soil microbes love it!
• Contains 3% available — and a minimum of 20% total — phosphoric acid (P2O5)

Available size: 50 lb Bag

Broadcast 50 lbs per 1,000 square feet or side dress around existing plants.

User’s Tip:
Calphos is fast-acting, similar to a superphosphate, and is relatively insoluble… so it will provide amazing results for a long time!

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