Mammoth P - Microbial Inoculant

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Standard Delivery £6.95*
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Product Name Qty Price
Mammoth P - 120ml
Mammoth P - 250ml
Mammoth P - 500ml
Mammoth P - 1L


Mammoth P boasts being the first organically derived microbial inoculant, and delivers a whole load of benefits for your plants. It maximises phosphorous and micronutrient cycling, giving bigger flower growth and better yields. In fact, you can expect on average a 16% increase in plant yield and a 6% increase in stem strength!

This formula has been developed and produced at a leading US university by Growcentia, a team of three PhD soil microbiologists, using next-generation technology. It has been further tested by Colorado growers and independent labs - all showing results with increased growth within plants.

The beneficial bacteria in Mammoth P act like micro bioreactors, working to continually produce enzymes that release nutrients. This helps to break down any locked out phosphorous, making it available to your plants. Then you have the increased levels of phosphorous helping to keep internodes shorter and instead focusing energy on flower production.

Mammoth P has been designed specifically to increase phosphorous availability throughout the bloom phase, and should be used as a supplement to your regular regime. Application during the clone and vegetative phase will also boost effectiveness however. The formulation has a close to neutral pH and runs clean in any system, with no blockages! It is also accredited OMRI for organic use.

The liquid formula can be applied directly to soil, coco or recirculating hydroponic systems alongside any other fertilisers.


  • Shake bottle well before use. Use with every watering, or with each reservoir fill throughout the blooming stage. Never mix concentrates.
  • Soil: Start with 0.16ml/L for seedlings/rooted cuttings, building up to 0.26ml/L once you get to more aggressive growth. When flowering, increase to 0.4ml/L – 1.06ml/L depending on the stage your plant is at. Once flushing, decrease to a rate of 0.26ml/L.
  • Hydro/Coco: Use at 0.16ml/L throughout both the growing and flowering cycles.

Full feeding table can be found here.

Please note that the 500ml and 1L bottles are only to order at the moment, so may encounter a slight delay on delivery time.

Delivery & Returns
Free Delivery
We are pleased to offer free standard shipping to UK Mainland on all orders over £65.00 *Heavy item surcharges are still applicable.
Next Day Delivery
In a hurry for your order? Order before 1 pm Mon - Thurs for next working day delivery *subject to stock availability T&C's apply.
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Free Returns
Faulty or damaged item? No problem, contact us on 0800 038 7100 or email customer service and we can arrange a free collection.
Plain Packaging
All parcels, no matter how big or small, are dispatched in plain packaging using black wrap that's secured using 'fragile' tape.
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Collect your online orders in as little as under an hour*! Simply pay online, choose your store & collect for free! Available from Manchester & Huddersfield (*subject to stock availability).
Brand Mammoth
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