• Liquid Calcium Phosphate — 500ml white bottle with kraft label: Dr Forest Liquid Calcium Phosphate Fertiliser 0-11-0.2
  • Liquid Calcium Phosphate — back of white bottle with Analysis panel and Directions for use
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Dr Forest

Liquid Phosphate Fertiliser UK | Calcium Phosphate Suspension | Foliar Spray

Liquid Phosphate Fertiliser UK | Calcium Phosphate Suspension | Foliar Spray

£19.99 GBP
£19.99 GBP
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  • ✓Handcrafted and dispatched from Stockport
  • ✓Made with organic ingredients, no slaughterhouse by-products

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Liquid micronised calcium phosphate — calcium and phosphorus together in one product

24.56% Calcium 10.71% Phosphorus 10.73% Silicon Recycled Plastic Bottle ACO Certified Organic Contains Fulvic Acid

Calcium and phosphorus are the two most important minerals for photosynthesis and sugar production in plants. But here is the problem: in ionic form, they are chemically incompatible. Mix dissolved calcium with dissolved phosphate and they precipitate out of solution instantly — locked up and unavailable. This is why no conventional liquid fertiliser can deliver both. This product solves that problem. By suspending micronised mineral calcium phosphate in colloidal form with fulvic acid, both elements coexist in a single plant-available liquid — something that is not possible with any dissolved salt formulation.

The source is natural mineral calcium phosphate — rich in calcium, phosphorus, silicon, manganese, and iron. Micronised and suspended in a fulvic acid carrier that improves foliar and root uptake while feeding soil biology. ACO certified organic (456AI). Suitable as a foliar spray, soil drench, or fertigation input across all growth stages from pre-planting to fruit fill.

24.56%Calcium (Ca)
10.71%Phosphorus (P)
10.73%Silicon (Si)
ACOCertified Organic

Full analysis

Nutrient Content (w/v)
Calcium (Ca) 24.56%
Silicon (Si) 10.73%
Total Phosphorus (P) 10.71%
— citrate insoluble P 7.56%
— citrate soluble P 3.15%
— water soluble P 20 mg/L
Manganese (Mn) 1.66%
Iron (Fe) 0.86%
Magnesium (Mg) 0.34%
Potassium (K) — organic 0.15%
Zinc (Zn) 0.14%
Copper (Cu) 162 mg/L

SG: 1.5 | pH: 6.5–8.5 | Appearance: thick, mid-brown liquid, citrus odour

What this calcium phosphate is used for

  • Delivering calcium and phosphorus together — the only liquid format that combines both minerals in plant-available form; eliminates the need for separate Ca and P applications that risk antagonistic lock-up
  • Boosting brix and sugar levels — calcium and phosphorus are both required for photosynthesis; supplying them together directly increases the plant's capacity to produce and transport sugars to fruit
  • Root development and establishment — phosphorus drives root cell division; calcium builds the cell walls of every new root tip; together they produce faster, stronger root establishment at planting
  • Flowering and fruit set — phosphorus fuels the energy metabolism of flowering; calcium strengthens pollen tube formation and fruit cell walls; critical from pre-flower through to fruit fill
  • Silicon for plant defence — 10.73% silicon strengthens cell walls, improves drought tolerance, and increases resistance to fungal attack; an often-overlooked mineral that most fertilisers do not supply
  • Bonus trace minerals — 1.66% manganese, 0.86% iron, plus zinc and copper; delivers meaningful micronutrient supplementation alongside the primary calcium and phosphorus
  • Soil biology stimulation — fulvic acid carrier feeds beneficial soil microorganisms and improves cation exchange capacity alongside delivering minerals

Why micronised mineral calcium phosphate instead of conventional phosphorus?

Micronised Mineral Suspension — this product

  • Calcium and phosphorus coexist in colloidal form — no precipitation
  • Natural mineral source: Ca, P, Si, Mn, Fe, Zn, Cu in one product
  • Fulvic acid improves foliar uptake and feeds soil biology
  • ACO certified organic — audited and compliant
  • No nitrogen included — apply P and Ca without forcing unwanted N
  • Compatible with most fertiliser inputs (non-ionic)

Conventional P Sources (MAP/DAP, Bone Meal)

  • MAP/DAP: highly acidic near the root zone; contains nitrogen whether you want it or not
  • Bone meal: slow to break down, coarse particle size, unavailable for weeks
  • Neither can be combined with calcium in liquid form — they precipitate
  • No silicon, no manganese, no fulvic acid — single-purpose inputs
  • Bone meal is a slaughterhouse by-product — not suitable for plant-based growing systems
Handcrafted in Stockport

Every Dr Forest product is made by hand in small batches at our workshop in Stockport, Greater Manchester. We source ingredients for quality, not cost. Supplied in recycled plastic bottles.

The science of calcium-phosphorus delivery from micronised mineral calcium phosphate

The incompatibility problem

Calcium (Ca²⁺) and phosphate (PO₄³⁻) ions are strongly attracted to each other. In any dissolved solution, they react immediately to form insoluble calcium phosphate precipitate — a white solid that drops out of solution and becomes unavailable to plants. This is why no conventional liquid fertiliser can contain both. It is also why adding soluble phosphate to calcium-rich soil often results in rapid lock-up. The colloidal micronised form sidesteps this chemistry entirely: the minerals are suspended as ultra-fine particles, not dissolved ions. They do not react with each other because they are not in ionic form.

01

Non-Ionic Colloidal Delivery

In a micronised mineral suspension, the mineral particles are ground to sub-200-micron size and held in liquid by fulvic acid and surfactant action. Because the calcium and phosphorus remain locked in their mineral matrix rather than dissolved as free ions, they cannot precipitate. Once applied to soil or leaf surfaces, the particles are broken down by root exudates, microbial activity, and organic acids into plant-available ionic forms — but by that point they are in the rhizosphere, not in a mixing tank. This is why micronised suspensions can deliver mineral combinations that dissolved solutions cannot.

02

Citrate Soluble Phosphorus

The phosphorus in this product exists in three forms: citrate insoluble (7.56%), citrate soluble (3.15%), and water soluble (20 mg/L). The citrate-soluble fraction is the most agronomically significant — it represents phosphorus that dissolves in the weak organic acids produced by plant roots and soil microorganisms. This is precisely the mechanism by which plants access phosphorus from rock-based sources. The high citrate-soluble fraction confirms that this phosphorus is genuinely plant-available through natural root activity, not just on paper.

03

Calcium — Cell Walls, Signalling, Sugar Transport

Calcium cross-links pectin chains in cell walls, providing structural rigidity. It also functions as a secondary messenger in cellular signalling pathways — triggering defence responses to pathogen attack, regulating stomatal opening, and controlling pollen tube growth during fertilisation. Calcium is phloem-immobile: once deposited in a cell wall, it cannot be redistributed. This means actively growing tissues — root tips, shoot tips, developing fruit — require continuous external supply. Foliar and drench application of micronised calcium delivers it directly to where demand is highest.

04

Phosphorus — Energy Currency of the Plant

Phosphorus is a component of ATP (adenosine triphosphate) — the molecule that stores and transfers energy in every living cell. Every metabolic reaction that requires energy — photosynthesis, sugar transport, cell division, root growth, flowering — depends on phosphorus. Deficient plants cannot produce enough ATP to power normal growth, resulting in stunted root systems, delayed flowering, and poor fruit set. Phosphorus is also a key component of DNA, RNA, and cell membranes.

05

Silicon — The Forgotten Defence Mineral

At 10.73%, the silicon content of this product is unusually high. Silicon deposits in cell walls as amorphous silica, forming a physical barrier against fungal penetration and insect feeding. Research consistently demonstrates that silicon-supplemented plants show improved resistance to powdery mildew, botrytis, and other foliar pathogens. Silicon also improves water use efficiency by reducing transpiration through thickened cuticles, and increases tolerance to heavy metal toxicity in contaminated soils.

06

Manganese and Iron — Hidden Bonus

At 1.66% Mn and 0.86% Fe, this product delivers meaningful micronutrient supplementation as a secondary benefit. Manganese is required for the water-splitting reaction in photosystem II — the first step of photosynthesis. Iron is essential for chlorophyll synthesis and electron transport. Both are commonly deficient in alkaline or calcareous soils. Receiving them alongside calcium and phosphorus from a single product simplifies the nutrition programme and reduces the number of separate inputs required.

Scientific References

  1. Marschner, P. (2012). Marschner's Mineral Nutrition of Higher Plants. 3rd ed. Academic Press.
  2. Ma, J.F. & Yamaji, N. (2006). Silicon uptake and accumulation in higher plants. Trends in Plant Science, 11(8), 392–397.
  3. White, P.J. & Broadley, M.R. (2003). Calcium in plants. Annals of Botany, 92(4), 487–511.
  4. Nardi, S. et al. (2009). Physiological effects of humic substances on higher plants. Soil Biol. Biochem., 41, 215–229.
  5. Liang, Y. et al. (2007). Importance of plant species and external silicon concentration to active silicon uptake and transport. New Phytologist, 172(1), 63–72.

How to use liquid micronised calcium phosphate: application rates & guide

Shake vigorously before every use

This is a heavy mineral suspension (SG 1.5) — significantly denser than water. The particles settle rapidly during storage. Shake vigorously for 15–20 seconds before measuring. Add to a small amount of warm water (20–30°C) and stir for at least 30 seconds before topping up. Maintain constant agitation during sprayer use. Use a coarse inline filter (500 micron / 35 mesh) to prevent blockages from contaminants.

Application rates — professional & commercial

Foliar spray — vegetables

Rate: 10 ml per litre of water (1 L per 100 L) | Max per hectare: 5 L/ha

Apply weekly or as required. Target all growth stages from planting through to fruit fill. Ensure thorough foliage coverage. Where higher water volumes are needed, do not exceed the maximum product rate per hectare.

Foliar spray — orchards & vineyards

Rate: 10 ml per litre of water (1 L per 100 L) | Max per hectare: 10 L/ha

Apply every 2–4 weeks or as required. Particularly valuable from pre-flower through fruit fill for calcium-dependent fruit quality and phosphorus-driven energy metabolism.

Foliar spray — ornamentals & turf

Rate: 10 ml per litre of water (1 L per 100 L) | Max per hectare: 7 L/ha

Apply every 2–4 weeks or as required. Silicon content improves disease resistance and structural strength in managed landscapes.

Broadacre crops & pasture

Rate: 2–3 L/ha in 60–100 L water | Frequency: As required

Adjust water volume depending on canopy closure. Apply at key growth stages based on crop monitoring and soil test data.

Fertigation & soil amelioration

Rate: 10–30 L/ha | Frequency: As required

Use the higher rate for soil amelioration where phosphorus and calcium deficiencies have been identified. Use the lower rate for maintenance fertigation. Always consider nitrogen and phosphorus crop requirements based on reliable soil test data.

Liquid inject — in-furrow at planting

Rate: 2–5 L/ha | Dilution: Minimum 1 part product to 3 parts water

Apply in-furrow at planting for immediate root-zone access to calcium and phosphorus. Rate depends on crop, row spacing, and soil type.

Spot spraying

Rate: 5 ml per litre of water (50 ml per 10 L) | Frequency: As required

For targeted foliar application to individual plants or small areas showing deficiency symptoms.

Application rates — home garden

Foliar spray & soil drench

Rate: 45 ml per 9-litre watering can | Coverage: Apply 1 litre of diluted mix per m²

Shake well before use. Dilute 45 ml into a 9-litre watering can. The diluted mix can be applied as a soil drench around the root zone or poured over foliage as a foliar feed. Repeat every 2–4 weeks or as required during the growing season.

Growth stage guide

All stages: Pre-planting through to fruit fill

Pre-planting: Drench soil before planting to build calcium and phosphorus reserves. Planting & establishment: Apply as a root drench to support root cell division. Vegetative growth: Every 2–4 weeks to support strong structural development. Pre-flower to fruit fill: Every 2–3 weeks to fuel flowering energy and fruit cell wall construction.

Step-by-step preparation

  1. Shake the bottle vigorously for 15–20 seconds. This is a heavy suspension — particles settle quickly.
  2. Measure the required volume. Home garden: 45 ml per 9L watering can. Use a measuring cup or syringe.
  3. Add to a small amount of warm water (20–30°C) and stir vigorously for 30 seconds. Then top up to the full volume.
  4. Apply immediately. For foliar, spray both leaf surfaces in early morning or late evening. For soil drench, apply at 1L per m² around the root zone.
  5. Clean equipment after use. The mineral particles can settle and clog sprayer nozzles if left to dry. Flush with clean water immediately after application.
Visible residue on foliage

Micronised mineral suspensions leave a visible residue on leaves and fruit. This is normal and not harmful. If produce appearance matters close to harvest, switch to soil drench application or spray earlier in the growing season.

Works well combined with…

Use alongside Yorkshire Polyhalite for slow-release K, Ca, Mg, and S in the soil. Pair with Micro-7 for complete chelated trace element coverage. Add Seaweed Powder for biostimulant activity and improved foliar wetting. Compatible with most fertiliser inputs due to the non-ionic colloidal format — but avoid combining with concentrated dissolved calcium or phosphate solutions. Jar-test before mixing with any new product.

Frequently asked questions

Dissolved calcium ions (Ca²⁺) and phosphate ions (PO₄³⁻) react to form insoluble calcium phosphate precipitate. It drops out of solution and becomes unavailable. This is basic chemistry — you cannot dissolve both in the same liquid. The micronised colloidal form solves this: the minerals are suspended as ultra-fine solid particles, not dissolved ions, so they cannot react with each other.
Natural mineral calcium phosphate — a mineral deposit rich in calcium phosphate, silicon, manganese, and iron. It is micronised (ground to ultra-fine particles) and suspended in a fulvic acid carrier. This is not a synthetic phosphate source. ACO certified organic.
Yes. The analysis shows 3.15% citrate-soluble phosphorus — this is the fraction that dissolves in the weak organic acids produced by plant roots and soil microbes. This is the standard measure of plant-available phosphorus from rock-based sources. The micronised particle size also accelerates breakdown compared to coarser rock phosphate products.
Three differences: particle size, mineral complexity, and source. This product is micronised to sub-200-micron particles — it breaks down in days, not months. It also delivers silicon (10.73%), manganese (1.66%), and iron (0.86%) that bone meal does not contain. And it is mineral-sourced — plant-based growers who avoid slaughterhouse by-products can use this without compromise.
Silicon deposits in cell walls as amorphous silica, creating a physical barrier against fungal penetration and insect feeding. Research consistently shows silicon-supplemented plants have improved resistance to powdery mildew, botrytis, and aphids. Silicon also improves water use efficiency and drought tolerance. Most fertilisers contain no silicon — the 10.73% in this product is a significant bonus.
No. This is a nitrogen-free source of calcium and phosphorus. This is a significant advantage when you need P and Ca without forcing additional nitrogen — conventional options like MAP, DAP, and calcium nitrate all include nitrogen whether you want it or not. Use this product when you need calcium and phosphorus at any growth stage without pushing vegetative growth.
Yes — micronised mineral suspensions leave a visible residue on foliage and fruit. This is harmless. If appearance matters close to harvest, use as a soil drench instead of foliar spray, or time foliar applications earlier in the growing season.
Yes, with appropriate precautions. Maintain constant agitation in the mixing tank. Use a coarse inline filter (500 micron / 35 mesh). The product passes through standard irrigation equipment under normal conditions. Flush lines with clean water after use to prevent residue buildup.
Store upright in a cool, dry place between 5–25°C, out of direct sunlight. Keep sealed. Shake vigorously before each use. Do not store below 5°C — sedimentation may occur. Do not store in diluted form — mix fresh for each application.
Yes. This product is supplied in recycled plastic bottles.

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