{"product_id":"organic-calcium-carbonate","title":"Garden Calcium Carbonate | Lime Alternative","description":"\u003c!-- Dr Forest — Micro Cal-Carb Micronised Calcium Carbonate Product Page --\u003e\n\u003c!-- Prefix: cc --\u003e\n\u003cstyle\u003e\n  .drf-wrap *, .drf-wrap *::before, .drf-wrap *::after { box-sizing: border-box; margin: 0; padding: 0; }\n  .drf-wrap { font-family: 'Jost', sans-serif; font-weight: 400; color: #2c2c2c; font-size: 14px; line-height: 1.65; width: 100%; max-width: 100%; overflow: hidden; }\n  :root { --drf-grn:#1B3D2F; --drf-grn-light:#E8F0EB; --drf-grn-mid:#4a7a5e; --drf-grn-dark:#0f2a1e; --drf-gold:#C5A55A; --drf-gold-light:#FAF7F0; --drf-cream:#F5F2EC; --drf-border:#d4cfc5; --drf-muted:#666; }\n  .drf-wrap h2 { font-family: 'Cormorant Garamond', serif; font-weight: 600; font-size: 1.9em; color: var(--drf-grn); line-height: 1.25; margin-bottom: 0.5em; }\n  .drf-wrap h3 { font-family: 'Cormorant Garamond', serif; font-weight: 600; font-size: 1.35em; color: var(--drf-grn); 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}\n  .drf-faq:last-child { border-bottom: none; }\n  .drf-faq input[type=\"checkbox\"] { display: none; }\n  .drf-faq-q { display: flex; justify-content: space-between; align-items: center; padding: 0.8em 0; cursor: pointer; font-weight: 600; color: var(--drf-grn); font-size: 0.95em; }\n  .drf-faq-q::after { content: '+'; font-size: 1.3em; font-weight: 300; color: var(--drf-gold); width: 1.5em; height: 1.5em; border-radius: 50%; background: var(--drf-grn-light); display: flex; align-items: center; justify-content: center; flex-shrink: 0; margin-left: 0.6em; }\n  .drf-faq-a { max-height: 0; overflow: hidden; transition: max-height 0.3s ease; font-size: 0.92em; color: #555; line-height: 1.7; }\n  .drf-faq-a \u003e div { padding: 0 0 1em; }\n  .drf-faq input:checked ~ .drf-faq-q::after { content: '−'; background: var(--drf-grn); color: #fff; }\n  .drf-faq input:checked ~ .drf-faq-a { max-height: 600px; }\n  .drf-refs { font-size: 0.78em; color: #888; line-height: 1.5; margin-top: 1.5em; padding-top: 0.8em; border-top: 1px solid var(--drf-border); }\n  .drf-refs ol { padding-left: 1.4em; margin: 0; }\n  .drf-refs li { margin-bottom: 0.3em; }\n  .drf-sep { border: none; border-top: 2px solid var(--drf-gold); margin: 1.5em 0; }\n  .drf-wrap table { width: 100%; border-collapse: collapse; margin: 1em 0; font-size: 0.92em; }\n  .drf-wrap table th { background: var(--drf-grn); color: #fff; font-weight: 600; padding: 0.6em 0.8em; text-align: left; font-size: 0.85em; letter-spacing: 0.04em; }\n  .drf-wrap table td { padding: 0.55em 0.8em; border-bottom: 1px solid var(--drf-border); }\n  .drf-wrap table tr:nth-child(even) td { background: var(--drf-grn-light); }\n\u003c\/style\u003e\n\n\u003cdiv class=\"drf-wrap\"\u003e\n\u003cdiv class=\"drf-tabs-wrap\"\u003e\n  \u003cinput type=\"radio\" name=\"drf-cc-tabset\" id=\"drf-cc-tab1\" checked\u003e\n  \u003cinput type=\"radio\" name=\"drf-cc-tabset\" id=\"drf-cc-tab2\"\u003e\n  \u003cinput type=\"radio\" name=\"drf-cc-tabset\" id=\"drf-cc-tab3\"\u003e\n  \u003cinput type=\"radio\" name=\"drf-cc-tabset\" id=\"drf-cc-tab4\"\u003e\n  \u003cdiv class=\"drf-tab-labels\"\u003e\n    \u003clabel for=\"drf-cc-tab1\"\u003eOverview\u003c\/label\u003e\n    \u003clabel for=\"drf-cc-tab2\"\u003eThe Science\u003c\/label\u003e\n    \u003clabel for=\"drf-cc-tab3\"\u003eHow to Use\u003c\/label\u003e\n    \u003clabel for=\"drf-cc-tab4\"\u003eFAQ\u003c\/label\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"drf-panels\"\u003e\n\n  \u003c!-- ═══════════ TAB 1 — OVERVIEW ═══════════ --\u003e\n  \u003cdiv class=\"drf-panel\" id=\"drf-cc-panel1\"\u003e\n    \u003ch2\u003eMicro Cal-Carb — 96% pure micronised calcium carbonate from natural limestone\u003c\/h2\u003e\n    \u003cdiv class=\"drf-badge-row\"\u003e\n      \u003cspan class=\"drf-badge drf-badge-green\"\u003e54.1% CaO Calcium\u003c\/span\u003e\n      \u003cspan class=\"drf-badge drf-badge-green\"\u003e96.2% CaCO₃ Purity\u003c\/span\u003e\n      \u003cspan class=\"drf-badge drf-badge-green\"\u003eMicronised to 63µ\u003c\/span\u003e\n      \u003cspan class=\"drf-badge drf-badge-green\"\u003epH Corrector\u003c\/span\u003e\n      \u003cspan class=\"drf-badge drf-badge-green\"\u003e91%+ Carbonic Solubility\u003c\/span\u003e\n      \u003cspan class=\"drf-badge drf-badge-green\"\u003eEU Organic Compliant\u003c\/span\u003e\n    \u003c\/div\u003e\n    \u003cp\u003eThe simplest and most concentrated calcium source available: \u003cstrong\u003e96.2% pure calcium carbonate\u003c\/strong\u003e from quarry-extracted natural limestone, mechanically crushed and micronised to 63 microns. No chemical processing, no additives, no fillers. At \u003cstrong\u003e54.1% CaO\u003c\/strong\u003e, this delivers more calcium per gram than gypsum (23% Ca), bone meal (~20% Ca), or any liquid calcium product on the market. The micronised particle size means it reacts rapidly in soil — far faster than agricultural lime — making it effective as both a calcium source and a fast-acting pH corrector for acidic soils.\u003c\/p\u003e\n    \u003cp\u003eThe \u003cstrong\u003ecarbonic solubility exceeds 91%\u003c\/strong\u003e — meaning over 91% of the calcium carbonate dissolves in the weak carbonic acid that naturally occurs in soil water. This is the measure that matters for plant availability: it tells you how much of the product will actually release calcium into the soil solution under normal growing conditions, not just in a laboratory acid bath.\u003c\/p\u003e\n\n    \u003cdiv class=\"drf-stats\"\u003e\n      \u003cdiv class=\"drf-stat\"\u003e\n\u003cspan class=\"drf-stat-number\"\u003e54.1%\u003c\/span\u003e\u003cspan class=\"drf-stat-label\"\u003eCaO Calcium\u003c\/span\u003e\n\u003c\/div\u003e\n      \u003cdiv class=\"drf-stat\"\u003e\n\u003cspan class=\"drf-stat-number\"\u003e96.2%\u003c\/span\u003e\u003cspan class=\"drf-stat-label\"\u003eCaCO₃ Purity\u003c\/span\u003e\n\u003c\/div\u003e\n      \u003cdiv class=\"drf-stat\"\u003e\n\u003cspan class=\"drf-stat-number\"\u003e63µ\u003c\/span\u003e\u003cspan class=\"drf-stat-label\"\u003eMicronised\u003c\/span\u003e\n\u003c\/div\u003e\n      \u003cdiv class=\"drf-stat\"\u003e\n\u003cspan class=\"drf-stat-number\"\u003e\u0026gt;91%\u003c\/span\u003e\u003cspan class=\"drf-stat-label\"\u003eCarbonic Solubility\u003c\/span\u003e\n\u003c\/div\u003e\n    \u003c\/div\u003e\n\n    \u003ch3\u003eFull mineral analysis\u003c\/h3\u003e\n    \u003ctable\u003e\n      \u003ctr\u003e\n\u003cth\u003eComponent\u003c\/th\u003e\n\u003cth\u003eContent\u003c\/th\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eCalcium carbonate (CaCO₃)\u003c\/td\u003e\n\u003ctd\u003e96.20%\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eCalcium (CaO)\u003c\/td\u003e\n\u003ctd\u003e54.10%\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSilica (SiO₂)\u003c\/td\u003e\n\u003ctd\u003e1.20%\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eIron (Fe₂O₃)\u003c\/td\u003e\n\u003ctd\u003e0.71%\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMagnesium (MgO)\u003c\/td\u003e\n\u003ctd\u003e0.48%\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003ePotassium (K₂O)\u003c\/td\u003e\n\u003ctd\u003e0.05%\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eManganese (MnO)\u003c\/td\u003e\n\u003ctd\u003e0.01%\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSodium (Na₂O)\u003c\/td\u003e\n\u003ctd\u003e0.01%\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/table\u003e\n    \u003cp\u003e\u003cem\u003eNeutralising value: 54  |  Carbonic solubility: \u0026gt;91%  |  95% passes 63µ sieve  |  EU organic compliant\u003c\/em\u003e\u003c\/p\u003e\n\n    \u003ch3\u003eWhat Micro Cal-Carb is used for\u003c\/h3\u003e\n    \u003cul class=\"drf-uses\"\u003e\n      \u003cli\u003e\n\u003cstrong\u003eConcentrated calcium source\u003c\/strong\u003e — at 54.1% CaO, this is the highest-concentration calcium product in the Dr Forest range; ideal when soil tests show calcium deficiency or when large calcium additions are needed without adding other nutrients\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003epH correction for acidic soils\u003c\/strong\u003e — calcium carbonate neutralises soil acidity; the micronised particle size and 91%+ carbonic solubility mean it acts far faster than coarse agricultural lime, correcting pH within weeks rather than months\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eFoliar and soil drench calcium\u003c\/strong\u003e — the 63µ micronised powder suspends in water for foliar spray or root drench application, delivering calcium directly where it is needed for cell wall construction\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eSoil mix amendment\u003c\/strong\u003e — incorporate into potting mixes, composts, and growing media to buffer pH and provide slow-release calcium throughout the growing season\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eMushroom cultivation\u003c\/strong\u003e — calcium carbonate is used in mushroom substrates as a pH buffer to maintain the alkaline conditions that favour mycelial growth while suppressing contaminant organisms\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eFruit trees, orchards, vines, and ornamentals\u003c\/strong\u003e — suitable for all crops; particularly valuable where calcium demand is high (tomatoes, peppers, brassicas, apples) or where soil pH is below 6.0\u003c\/li\u003e\n    \u003c\/ul\u003e\n\n    \u003ch3\u003eWhy micronised limestone instead of agricultural lime?\u003c\/h3\u003e\n    \u003cdiv class=\"drf-compare\"\u003e\n      \u003cdiv class=\"drf-compare-box\"\u003e\n        \u003ch4\u003eMicronised Calcium Carbonate — Micro Cal-Carb\u003c\/h4\u003e\n        \u003cul\u003e\n          \u003cli\u003e96.2% CaCO₃ purity — minimal impurities\u003c\/li\u003e\n          \u003cli\u003eMicronised to 63µ — reacts rapidly in soil, effective within weeks\u003c\/li\u003e\n          \u003cli\u003e91%+ carbonic solubility — genuinely plant-available\u003c\/li\u003e\n          \u003cli\u003eFine enough to suspend in water for foliar spray or drench\u003c\/li\u003e\n          \u003cli\u003eCan be incorporated into soil mixes at precise rates\u003c\/li\u003e\n          \u003cli\u003eNo chemical processing — quarry-extracted and mechanically ground\u003c\/li\u003e\n        \u003c\/ul\u003e\n      \u003c\/div\u003e\n      \u003cdiv class=\"drf-compare-box\"\u003e\n        \u003ch4\u003eStandard Agricultural Lime\u003c\/h4\u003e\n        \u003cul\u003e\n          \u003cli\u003eCoarse particle size — takes 6–12 months to fully react\u003c\/li\u003e\n          \u003cli\u003eVariable purity — often 70–85% CaCO₃ with clay and silica fillers\u003c\/li\u003e\n          \u003cli\u003eCannot be suspended in water for liquid application\u003c\/li\u003e\n          \u003cli\u003eToo coarse for precise soil mix formulation\u003c\/li\u003e\n          \u003cli\u003eSlow pH correction — may take a full season to reach target\u003c\/li\u003e\n        \u003c\/ul\u003e\n      \u003c\/div\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"drf-callout\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eHandcrafted in Stockport\u003c\/span\u003e\u003cp\u003eEvery Dr Forest product is made by hand in small batches at our workshop in Stockport, Greater Manchester. We source ingredients for quality, not cost.\u003c\/p\u003e\n\u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003c!-- ═══════════ TAB 2 — THE SCIENCE ═══════════ --\u003e\n  \u003cdiv class=\"drf-panel\" id=\"drf-cc-panel2\"\u003e\n    \u003ch2\u003eThe science of calcium carbonate: pH correction \u0026amp; calcium delivery\u003c\/h2\u003e\n    \u003ch3\u003eWhy particle size determines everything\u003c\/h3\u003e\n    \u003cp\u003eCalcium carbonate is the most common liming material in agriculture. But its effectiveness depends almost entirely on particle size. A coarse limestone chip can sit in soil for years without fully dissolving. The same mineral ground to 63 microns has an enormously greater surface area exposed to soil acids, root exudates, and microbial activity — accelerating dissolution from months to weeks. This is why micronised limestone acts as both a rapid pH corrector and a plant-available calcium source, while coarse ag-lime is essentially a long-term soil amendment with minimal short-term benefit.\u003c\/p\u003e\n    \u003chr class=\"drf-sep\"\u003e\n    \u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e01\u003c\/span\u003e\u003ch4\u003eThe Dissolution Chemistry\u003c\/h4\u003e\n\u003cp\u003eCalcium carbonate dissolves in acid: CaCO₃ + 2H⁺ → Ca²⁺ + H₂O + CO₂. In soil, the acid comes from three sources: carbonic acid (CO₂ dissolved in soil water), organic acids from root exudates, and organic acids from microbial metabolism. The reaction consumes hydrogen ions (H⁺) — which is precisely how it raises pH. Each molecule of CaCO₃ that dissolves removes two hydrogen ions from the soil solution and releases one calcium ion. The 91%+ carbonic solubility of this product confirms that over 91% of the CaCO₃ dissolves under these natural soil conditions.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e02\u003c\/span\u003e\u003ch4\u003eCalcium — Cell Walls, Signalling \u0026amp; Defence\u003c\/h4\u003e\n\u003cp\u003eCalcium cross-links pectin chains in cell walls, providing the structural rigidity that prevents fruit splitting, blossom end rot, tip burn, and bitter pit. It also functions as a secondary messenger in cell signalling — triggering defence responses to pathogen attack, regulating stomatal opening, and controlling pollen tube growth. Calcium is phloem-immobile: once deposited in a cell wall, it cannot be moved. Actively growing tissues need continuous external supply. Micronised CaCO₃ applied as a foliar spray or drench delivers calcium directly to where demand is highest.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e03\u003c\/span\u003e\u003ch4\u003epH and Nutrient Availability\u003c\/h4\u003e\n\u003cp\u003eSoil pH governs the availability of almost every plant nutrient. Below pH 6.0, phosphorus becomes increasingly locked up with aluminium and iron. Molybdenum availability drops sharply. Aluminium and manganese can reach toxic levels. Calcium and magnesium leach faster than they are replaced. Raising pH from 5.5 to 6.5 with calcium carbonate doesn't just add calcium — it unlocks the phosphorus, molybdenum, and other nutrients that were already present in the soil but chemically unavailable. This is often the single most cost-effective intervention in acidic soil management.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e04\u003c\/span\u003e\u003ch4\u003eSurface Area \u0026amp; Reaction Speed\u003c\/h4\u003e\n\u003cp\u003eA 1 cm limestone chip has approximately 6 cm² of surface area. The same mass ground to 63µ particles has a surface area measured in thousands of square centimetres. Chemical reactions happen at surfaces — the more surface exposed to soil acids, the faster the CaCO₃ dissolves and the faster pH rises. Standard agricultural lime (2–4 mm particles) may take 6–12 months to fully react. Micronised limestone at 63µ achieves measurable pH correction within 2–4 weeks under active growing conditions.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e05\u003c\/span\u003e\u003ch4\u003e96% Purity — Why It Matters\u003c\/h4\u003e\n\u003cp\u003eLower-grade liming materials contain 70–85% CaCO₃ with the balance being clay, silica, and other inert fillers. These fillers contribute no calcium, no pH correction, and no agronomic benefit — they are dead weight. At 96.2% CaCO₃, this product delivers 54.1% CaO per kilogram applied. You need less product per square metre to achieve the same result, and the dosing calculations are more precise because almost everything in the bag is active ingredient.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e06\u003c\/span\u003e\u003ch4\u003eSoil Biology \u0026amp; Calcium Carbonate\u003c\/h4\u003e\n\u003cp\u003eMost beneficial soil bacteria and fungi prefer a pH of 6.0–7.0. In acidic soils (pH \u0026lt;5.5), bacterial activity declines sharply while pathogenic fungi — particularly Fusarium and Pythium — thrive in the absence of bacterial competition. Correcting soil pH with calcium carbonate shifts the microbial balance in favour of beneficial organisms. The calcium itself also improves soil structure by flocculating clay particles, improving aggregation, aeration, and water infiltration.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-refs\"\u003e\n\u003ch4\u003eScientific References\u003c\/h4\u003e\n\u003col\u003e\n      \u003cli\u003eMarschner, P. (2012). \u003cem\u003eMarschner's Mineral Nutrition of Higher Plants\u003c\/em\u003e. 3rd ed. Academic Press.\u003c\/li\u003e\n      \u003cli\u003eWhite, P.J. \u0026amp; Broadley, M.R. (2003). Calcium in plants. \u003cem\u003eAnnals of Botany\u003c\/em\u003e, 92(4), 487–511.\u003c\/li\u003e\n      \u003cli\u003eHolland, J.E. et al. (2018). Liming impacts on soils, crops and biodiversity in the UK. \u003cem\u003eSoil Use and Management\u003c\/em\u003e, 34, 504–519.\u003c\/li\u003e\n      \u003cli\u003eMengel, K. \u0026amp; Kirkby, E.A. (2001). \u003cem\u003ePrinciples of Plant Nutrition\u003c\/em\u003e. 5th ed. Kluwer Academic.\u003c\/li\u003e\n    \u003c\/ol\u003e\n\u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003c!-- ═══════════ TAB 3 — HOW TO USE ═══════════ --\u003e\n  \u003cdiv class=\"drf-panel\" id=\"drf-cc-panel3\"\u003e\n    \u003ch2\u003eHow to use Micro Cal-Carb: application rates \u0026amp; guide\u003c\/h2\u003e\n    \u003cdiv class=\"drf-callout drf-callout-gold\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eRate depends on soil test results\u003c\/span\u003e\u003cp\u003eThe correct application rate for pH correction depends on your current soil pH, target pH, soil type (clay vs sand), and buffering capacity. The rates below are general guidelines. For precise liming, have your soil tested and calculate the requirement based on the neutralising value (54) and your soil's lime requirement figure.\u003c\/p\u003e\n\u003c\/div\u003e\n\n    \u003ch3\u003eApplication methods\u003c\/h3\u003e\n    \u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eFoliar spray or soil drench\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 0.5–1 g per litre of water  |  \u003cstrong\u003eFrequency:\u003c\/strong\u003e As required\u003c\/div\u003e\n\u003cp\u003eAdd the powder to water and stir vigorously. The micronised particles suspend readily at this concentration. Apply as a foliar spray or pour directly around the root zone. For foliar use, strain through a fine sieve before adding to a sprayer to prevent nozzle blockages. Delivers calcium directly to actively growing tissue.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eFruit trees \u0026amp; established shrubs\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 0.5 kg per m²  |  \u003cstrong\u003eTiming:\u003c\/strong\u003e Late winter \/ early spring, or after harvest\u003c\/div\u003e\n\u003cp\u003eScatter evenly under the canopy from trunk to drip line. Lightly rake into the top few centimetres of soil and water in. The micronised particles begin reacting within days.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eOrchards\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 0.6 kg per m²  |  \u003cstrong\u003eTiming:\u003c\/strong\u003e Late autumn or early spring\u003c\/div\u003e\n\u003cp\u003eBroadcast over the root zone. Work into the soil surface where possible. The higher rate reflects the greater calcium demand of productive orchard trees and the need for ongoing pH management.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eLawns \u0026amp; turf\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 0.4 kg per m²  |  \u003cstrong\u003eTiming:\u003c\/strong\u003e Autumn or early spring\u003c\/div\u003e\n\u003cp\u003eScatter evenly over the lawn surface. The fine powder settles into the turf canopy with watering or rain. Improves soil pH and calcium availability for root development and cold tolerance.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eSoil mixes \u0026amp; growing media\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eGuideline:\u003c\/strong\u003e 1–3 g per litre of compost or growing medium\u003c\/div\u003e\n\u003cp\u003eIncorporate thoroughly before planting. Buffers pH and provides slow-release calcium throughout the growing season. Start at the lower end for mixes that already contain lime; use the higher end for peat-based or coir-based media that tend to be acidic.\u003c\/p\u003e\n\u003c\/div\u003e\n\n    \u003ch3\u003eStep-by-step for liquid application\u003c\/h3\u003e\n    \u003col class=\"drf-steps\"\u003e\n      \u003cli\u003e\n\u003cstrong\u003eMeasure the powder.\u003c\/strong\u003e 0.5–1 g per litre. A level ½ teaspoon is approximately 1–1.5 g depending on how tightly packed.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eAdd to warm water and stir vigorously.\u003c\/strong\u003e The micronised particles suspend readily but will settle if left standing. Maintain agitation.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eFor foliar use, strain first.\u003c\/strong\u003e Pour through a fine sieve or muslin into the sprayer. Apply as a fine mist to both leaf surfaces.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eFor root drench, pour directly.\u003c\/strong\u003e Apply around the root zone using a watering can. No straining needed.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eFor dry application, scatter and rake in.\u003c\/strong\u003e Spread evenly, work into the top 2–5 cm of soil, and water thoroughly.\u003c\/li\u003e\n    \u003c\/ol\u003e\n\n    \u003cdiv class=\"drf-callout\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eWorks well combined with…\u003c\/span\u003e\u003cp\u003eUse alongside \u003cstrong\u003eDr Forest Cal-Mag Supplement\u003c\/strong\u003e for combined calcium and magnesium delivery with boron. Pair with \u003cstrong\u003eYorkshire Polyhalite\u003c\/strong\u003e for a complete secondary nutrient package (Ca, Mg, K, S). For liquid foliar calcium during fruiting, add \u003cstrong\u003eCal-Mino\u003c\/strong\u003e amino acid chelated calcium. \u003cstrong\u003eDo not mix with phosphate fertilisers in liquid form\u003c\/strong\u003e — calcium and phosphate precipitate when dissolved together.\u003c\/p\u003e\n\u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003c!-- ═══════════ TAB 4 — FAQ ═══════════ --\u003e\n  \u003cdiv class=\"drf-panel\" id=\"drf-cc-panel4\"\u003e\n    \u003ch2\u003eFrequently asked questions\u003c\/h2\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq1\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq1\"\u003eIs this the same as agricultural lime?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eSame mineral — calcium carbonate — but fundamentally different particle size and purity. Agricultural lime is typically 2–4 mm particles at 70–85% purity. This product is micronised to 63µ (95% passes a 63-micron sieve) at 96.2% purity. The finer particle size means it reacts in weeks rather than months. The higher purity means more calcium per gram applied.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq2\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq2\"\u003eHow is this different from gypsum?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eGypsum (calcium sulphate) provides calcium and sulphur but does \u003cstrong\u003enot\u003c\/strong\u003e raise soil pH — it is pH-neutral. Calcium carbonate provides calcium and \u003cstrong\u003edoes\u003c\/strong\u003e raise pH by neutralising soil acidity. Use gypsum when calcium is needed without pH change (e.g. in alkaline soils or to improve clay structure). Use Micro Cal-Carb when you need both calcium and pH correction.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq3\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq3\"\u003eWill it raise my soil pH too high?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eCalcium carbonate is self-limiting. It dissolves in acid conditions but becomes increasingly insoluble as pH rises above 7.0. It is very difficult to over-lime with CaCO₃ — the reaction slows and effectively stops as the soil approaches neutral pH. This is a safer liming material than quicklime (CaO) or hydrated lime (Ca(OH)₂), which can raise pH rapidly and excessively.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq4\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq4\"\u003eHow quickly does it work?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eThe micronised particle size (63µ) means the calcium carbonate begins dissolving within days of contact with moist soil. Measurable pH change typically occurs within 2–4 weeks under active growing conditions. Coarse agricultural lime may take 6–12 months to achieve the same result.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq5\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq5\"\u003eCan I use this as a foliar spray?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eYes. At 0.5–1 g per litre, the micronised powder suspends in water for foliar application. Strain through a fine sieve before adding to a sprayer. This delivers calcium directly to leaves and developing fruit — useful for preventing blossom end rot, tip burn, and bitter pit where root uptake is insufficient.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq6\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq6\"\u003eCan I mix it with other fertilisers?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eAs a dry amendment, yes — it mixes well with granular fertilisers and soil mixes. In liquid form, \u003cstrong\u003edo not mix with phosphate fertilisers\u003c\/strong\u003e — dissolved calcium and phosphate react to form insoluble calcium phosphate. Also avoid mixing with acidic liquid feeds, as the acid will react with the carbonate. Compatible with most granular and dry organic fertilisers.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq7\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq7\"\u003eIs this suitable for mushroom cultivation?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eYes. Calcium carbonate is widely used in mushroom substrates as a pH buffer. It maintains the alkaline conditions that favour mycelial growth while suppressing contaminant organisms. The micronised form mixes more uniformly through the substrate than coarser lime products.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq8\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq8\"\u003eHow much do I need for pH correction?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eThis depends on your current soil pH, target pH, soil type, and organic matter content. Clay soils and high-organic-matter soils require more lime to shift pH than sandy soils. As a starting point: 200–400 g\/m² will typically raise the pH of a light sandy soil by 0.5–1.0 units. For precise calculations, have your soil tested and use the neutralising value (54) to calculate the requirement.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-cc-faq9\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-cc-faq9\"\u003eIs this safe for all plants?\u003c\/label\u003e\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eCalcium carbonate is safe for all plants at recommended rates. However, acid-loving plants (blueberries, azaleas, rhododendrons, camellias) prefer a low pH and should not be limed. Do not apply to ericaceous or acid-loving species.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Dr Forest","offers":[{"title":"500g","offer_id":45735732838587,"sku":null,"price":7.0,"currency_code":"GBP","in_stock":true},{"title":"1.5kg","offer_id":45735732871355,"sku":null,"price":13.0,"currency_code":"GBP","in_stock":true},{"title":"3kg","offer_id":45735732904123,"sku":null,"price":20.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0049\/8194\/8504\/files\/organic-micro-cal-carb-micronised-calcium-carbonate-ph-8-fast-663.webp?v=1772229345","url":"https:\/\/www.drforest.co.uk\/products\/organic-calcium-carbonate","provider":"Dr Forest","version":"1.0","type":"link"}