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CIRP aka Christmas Island Rock Phosphate

CIRP or Christmas Island Rock phosphate, is mined from rocks made of sea bird poop compiled over millions of years that contain phosphorus and is used to make organic phosphate fertilizers that many organic gardeners utilize. CIRP contains 32% Phosphate and 5% Calcium Carbonate.

These fertilizers are commonly called “rock dust” and provide just the right amount of nutrients to make plants strong and healthy. The use of rock phosphate for gardens is a common practice for both flowers as well as vegetables. Flowers love an application of rock phosphate early in the season and will reward you with big, vibrant blooms.

Christmas Island Rock Phosphate’s combination of fluorohydroxyapatite, calcium iron and aluminium phosphates make it a highly sought-after phosphate product, which provides benefits in a range of fertiliser manufacturing processes. Its relatively high total phosphorus oxide (P2O5) level improves the analysis of many straight and compound fertilisers, and its iron and aluminium content improves the granule strength of a range of acidulated fertilisers. In addition, its reactive characteristics provide advantages for compacted fertilisers that do not undergo chemical processes.

What it is used for

CIRP provides essential plant nutrients for your garden.

A must have fertiliser for your edible garden

How to Apply

  1. BEST For your compost: Adding rock dust to compost will add available nutrients for plants. The phosphorus in rock phosphate requires acidic soil to be accessible. Alkaline soil can make the fertilizer almost useless. To speed up the process, you can add the CIRP to compost. The acidic nature of compost can allow the chemical bonds to loosen, thereby making phosphorus more accessible to the roots. 

  2. CIRP are best applied before planting (preparation of the vegetables beds) and after your plants have stabilised in its vegetable beds . Estimates are about 10 pounds (4.5 kg.) per 100 square feet (30.5 m.)

More about CIRP:

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